Alleged CRU Emails - 25 results below

The below are part of a series of alleged emails from the Climate Research Unit at the University of East Anglia, released on 20 November 2009.

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Original Filename: 1038842251.txt | Return to the index page | Permalink | Later Emails

From: Eystein Jansen <Jansen@xxxxxxxxx.xxx>
To: Laurent Labeyrie <Laurent.Labeyrie@xxxxxxxxx.xxx>, Keith Alverson <keith.alverson@xxxxxxxxx.xxx>, Keith Briffa <k.briffa@xxxxxxxxx.xxx>, Rick Battarbee <r.battarbee@xxxxxxxxx.xxx>, didier.paillard@xxxxxxxxx.xxx, Dominique Raynaud <domraynaud@xxxxxxxxx.xxx>, jean jouzel <jouzel@xxxxxxxxx.xxx>, Chappellaz Jerome <jerome@xxxxxxxxx.xxx>, Gerald Ganssen <gang@xxxxxxxxx.xxx>, Jean Marc Barnola <barnola@xxxxxxxxx.xxx>, Ralph Schneider <rschneid@xxxxxxxxx.xxx>
Subject: FP6 - NoE Dynamics of Climate Changes (DOCC)
Date: Mon, 2 Dec 2002 10:17:31 +0100
Cc: martin.miles@xxxxxxxxx.xxx, b.balino@xxxxxxxxx.xxx

<x-flowed>
Dear friends,

I assume many of you have followed the development of the work
programme for FP6, which have been quite dramatic at times for our
field. The end result is not particularly good, and the whole area of
Global Change has been cut by comparuison with FP5. I talked with
Anver Ghazi last week, and what I know stems from this and from the
Nov. 18 version of the work programme.
The will be no opening for climate dynamics in the first call (Dec. 17).
The second call due in June /July with a deadline in October 2003
will include some paleoclimate openings:
- STREPS for novel paleoreconstructions methods (i.e. a few of the
normal projects of previous FPs) - but remember: 75% of funding goes
to New Instruments: Integrated Projects and NoEs).
- Hot spots in the climate system, including the thermohaline
circulation and the Arctic.

Brussels will not issue anything now about the thrird call, but
according to Ghazi they plan to invite for either an NoE or an IP in
climate dynamics with emphasis on past climate change at that point.
Call will be in 2004. But things can change with this call.
Thus we have quite some time to discuss if we shall go forward with
DOCC or go for IP. The overall size of the IPs have been
substantially reduced, so if we try an IP or an NoE either will need
to be more focussed in terms of science and in terms of partnership
than our Expression of interest.

Ceers,

Eystein
--
______________________________________________________________
Eystein Jansen
Professor/Director
Bjerknes Centre for Climate Research and
Dep. of Geology, Univ. of Bergen
All

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From: "Eystein Jansen" <eystein.jansen@xxxxxxxxx.xxx>
To: "Keith Briffa" <k.briffa@xxxxxxxxx.xxx>
Subject: Re: Re: Holclim follow up
Date: Mon 7 Apr 2003 16:04

Dear Keith.
I had a chat with Dominique Reynaud on this matter today here in Nice. His impression is the same, but added that he thinks Brussels would insist on a NoE rather than an IP. If we wish to have an IP it needs lobbying it seems. He told about the meeting in Brussels inJune. I am not invited as far as I can tell. Dominique mentioned that Nick Shackleton would be there and I will talk with him. The key thing would be to sort out what the most exciting science our community can offer when we integrate the communities.
In terms of meetings it seems to depend alittle of what comes out of the June meeting in Brusseks.
Cheers
Eystein
>---- Original Message ---
>From: Keith Briffa <k.briffa@xxxxxxxxx.xxx>
>To: Eystein Jansen <eystein.jansen@xxxxxxxxx.xxx>
>Subject: Re: Holclim follow up
>
>
>Eystein
>your point is exactly correct , that only one project (and I believe it=20
>should be an IP) will be allowed and with the shrinking general scale of=20
>these things, it likely needs to be very clearly focused (on integrating=20
>evidence and providing some state-of-the-art product on climate history and=
>=20
>its causes) . I am not in Nice (have to go to 2 other meetings in May) . I=
>=20
>am still leaning towards your institute co-ordinating this . I have not=20
>discussed anything with the rest of the HOLIVAR committee.
>We do need some sort of meeting but only small - there is no chance of a 25=
>=20
>million Euro project and many people are likely to be disappointed . I have=
>=20
>to be in Brussels for a meeting with Brelen in June . What are you thinking=
>=20
>about , re. a meeting?
>Keith
>At 10:01 PM 4/3/03 +0200, you wrote:
>>Dear Keith,
>> I was just wondering whether you were coming the the EGS meeting in Nice=
>=20
>> next week, in order for us to exchange some ideas about how to proceed=20
>> for FP6. Recent rumors says that the palaeoclimate variablity item is in=
>=20
>> the books for the third call, and that the call will be issued by the=20
>> turn of the year, thus we should start discussing how to proceed. So far=
>=20
>> my DOCC initiative is dormant, and I am more inclined to develop or take=
>=20
>> part in developing an IP if the call for proposals allow for one. But the=
>=20
>> size of these IPs seems to be diminishing, hence a careful focussing=20
>> needs to be undertaken in order for there to be resources for the science=
>=20
>> teams. I would be happy to discuss idea with you on this in Nice or=20
>> sometime else if you=B4re not there.
>>
>>Cheers,
>>Eystein
>>
>>
>>
>>Eystein Jansen
>>prof/director
>>Bjerknes Centre for Climate Research
>>All=E9gaten 55, N5007 Bergen, Norway
>>tel: +4755583491/secr:+4755589803/fax:+4755584330
>>eystein.jansen@xxxxxxxxx.xxx, www.bjerknes.uib.no
>
>--
>Professor Keith Briffa,
>Climatic Research Unit
>University of East Anglia
>Norwich, NR4 7TJ, U.K.
>
>Phone: xxx xxxx xxxx
>Fax: xxx xxxx xxxx
>
>http://www.cru.uea.ac.uk/cru/people/briffa/
>
>

Original Filename: 1057368583.txt | Return to the index page | Permalink | Later Emails

From: Eystein Jansen <eystein.jansen@xxxxxxxxx.xxx>
To: Keith Briffa <k.briffa@xxxxxxxxx.xxx>
Subject: Re: FP6-news?
Date: Fri, 4 Jul 2003 21:29:43 +0200

<x-flowed>
Dear Keith, thanks for the update. I think I am reading much the same
message as you do. I also agree that we need focus, and not too many
groups involved. In terms of where the focus should be I agree that
DOCC is too wide, and my feeling now is to dissolve it and reorganise
under another heading with fewer groups, perhaps as an IP if Brussels
allows. I do not have any preconceived notions as to where the
co-ordinations hould lie.
I agree with you that integration with biogeochemistry is not
straight forward with Holocene climate variability except for the
vegetation feedback which may be important.
I also know of one other palaeo-based initiative, ICON, dealing with
the thermohaline circulation, coordinated by Rainer Zahn. We are
involved. This will be submitted for the call just launched under the
hot spots in the climate system heading, but may be brought over to
the next call if unsuccessful (probably). We are involved there with
a number of modelling centres and many of the palaeoceanography labs.

I guess we should discuss a bit further after summer has passed what
to do. I am very keen on the science of Holclim and hope to be able
to develop this initiative with you and others.
Last thing - any idea of when the conference Brussels wants is going
to happen?.
I am away for two weeks on the Greek islands, but then I am back again.

Cheers,
Eystein

>Eystein
>I seem to keep getting distracted this week so I have not phoned
>again. I can say the basics here though. I went to the meeting that
>was also attended by Berger, Raynaud, Shackleton , Starkel and
>Zorita
>(in place of Von Storch). The rationale for the meeting was nothing
>more than The EC (Hans Brelen) felt that they ought to be organising
>a palaeoclimate conference, but there was some hinting that this
>might signal the new call (in Sept 04) but not imply any weighting
>in the appraisal of proposals. It seems definite that there will be
>money for a single (new instrument) project only , as we supposed .
>Some at the meeting spoke about a range of time scales and possible
>subject foci for the conference (and by implication also for the
>call) but I still feel strongly , on the evidence of other projects
>that I have heard are to be funded , that the need is for a sharper
>focus than was involved in our DOCC concept , and that the HOLIVAR
>approach is the optimum way forward. The problem will be scale of
>initiative xxx xxxx xxxxmillion seems a maximum likely request , with
>perhaps xxx xxxx xxxxa likely maximum award). The unified data / modelling
>route, as outlined in the HOLCLIM NoI seems the most likely
>candidate still. Obviously there remain difficulties even with this
>, such as geographic focus , use of the integrated data for defining
>future climate probabilities and links with socio-economic (impacts)
>community. This is also likely to clash with the direct interests of
>some major palaeoclimate scientists who focus on longer time scales
>and stronger climate and response signals. It is easier to think of
>climate forcings and the interaction of bio-geochemical cycles at
>glacial /interglacial time scales , but I am not convinced that this
>type of work would be a practical inclusion in this call. This is
>still my opinion , but an admittedly (unashamedly) biased one.
>Keith
>
>
>At 07:34 PM 6/19/03 +0200, you wrote:
>>Dear Keith,
>>I wonder if there are any news around the meeting with Brelen on
>>FP6 that can be used. Lots of rumors around and not much specific
>>knowledge, so if you have an update I

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From: Keith Alverson <keith.alverson@xxxxxxxxx.xxx>
To: Rick Battarbee <r.battarbee@xxxxxxxxx.xxx>, Eystein Jansen <eystein.jansen@xxxxxxxxx.xxx>, Keith Briffa <k.briffa@xxxxxxxxx.xxx>
Subject: Re: fp6
Date: Mon, 07 Jul 2003 09:57:05 +0200

Dear Rick, Keith and Eystein,

It is certainly good news that FP6 will have a climate change and paleo
related call. My personal feeling is that whatever paleo proposal(s)
eventually do go in that it would be a good thing to specifically include
the PAGES office in Bern as a participant in the network. This would, I
believe, help the network by providing an international context and the many
PAGES resources for outreach within Europe, and inclusion of non-europeans.
On the other side of the coin, PAGES is currently seeking to broaden our
support base beyond USA and Switzerland and participation in an EU framework
proposal would be an ideal way to do this, given the strong representation
of European scientists within the PAGES community. If, however, you have
reason to believe that explicit inclusion of the PAGES office in the list of
partner organizations would reduce the chance of success of such a proposal,
then of course don't do it. Basically, I would much appreciate being kept in
the loop with your plans and am happy to participate, and offer the help of
PAGES, in any way I that you deem useful.

Keith

on 07/04/2003 08:08 PM, Rick Battarbee at r.battarbee@xxxxxxxxx.xxx wrote:

> Dear all,
>
> We have just come to the end of a very rewarding and successful HOLIVAR
> training course here with a very good bunch of young scientists from across
> Europe all involved in some aspect of high resolution Holocene change and
> embracing climate modelling, and climate reconstruction both from marine
> and continental records. We shall be putting details on the HOLIVAR
> website soon. (I should also say that Andy Lotter's workshop in April on
> age modelling was also very successful, and details are now on the web)
>
> I will produce a more detailed report on HOLIVAR activities and plans for
> the future shortly, and there should be plenty to discuss at our next
> Steering Committee meeting on October 3rd (please check your diaries -
> Innsbruck October 3rd).
>
> The main reason for writing, however, is to alert you to the probability of
> a call for proposals on climate change by the EU in FP6 for 2004, and the
> need for us to begin thinking again about an integrated project based on
> HOLIVAR. If you remember Keith Briffa submitted on behalf of the HOLIVAR
> community an Expression of Interest called HOLCLIM that found much favour
> at the time with the EU. Although I have not spoken at length with Keith
> about this I'm sure he is keen to see a project based on HOLCLIM taken
> forwards.
>
> Whilst we can not be sure of the detailed wording of the call I think it is
> nevertheless not too soon to begin designing the project It would be very
> useful to have your thoughts on how to proceed so that we can prepare a
> document for discussion on October 3rd. One issue is the potential overlap
> with DOCC. Eystein, what is your view on this? I'm sure there will be
> only one "palaeo" project funded and therefore if we simply followed the
> original intentions, HOLCLIM and DOCC would be in competition. And putting
> the two together would be difficult, HOLCLIM is an IP, and DOCC a NoE and
> the research community potentially involved would be huge, especially in
> relation to the budget which may be no more than 10 million euros.
>
> Please let me have your views, and then I will get together with Keith and
> come up with some kind of proposed way forwards for the meeting in October.
>
> Best wishes to all,
>
> Rick
> Professor R.W. Battarbee
> Environmental Change Research Centre
> University College London
> 26 Bedford Way, London WC1H 0AP, UK.
> Tel. +44 (0xxx xxxx xxxx, Fax +44 (0xxx xxxx xxxx
> http://www.geog.ucl.ac.uk/ecrc/
>

--
Keith Alverson
Executive Director
PAGES International Project Office
B

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From: Keith Briffa <k.briffa@xxxxxxxxx.xxx>
To: John.Birks@xxxxxxxxx.xxx,masson@xxxxxxxxx.xxx,dirk.verschuren@xxxxxxxxx.xxx,Laurent.Labeyrie@xxxxxxxxx.xxx,juerg.beer@xxxxxxxxx.xxx,A.Lotter@xxxxxxxxx.xxx,t.osborn@xxxxxxxxx.xxx,hufischer@xxxxxxxxx.xxx ,dan.charman@xxxxxxxxx.xxx,karin@xxxxxxxxx.xxx
Subject: IMPRINT
Date: Fri Aug 13 17:37:xxx xxxx xxxx
Cc: wanner@xxxxxxxxx.xxx,esper@xxxxxxxxx.xxx, Basil.Davis@xxxxxxxxx.xxx,sigfus@xxxxxxxxx.xxx,guiot@xxxxxxxxx.xxx,Ian.Snowball@xxxxxxxxx.xxx,antti.ojala@xxxxxxxxx.xxx,atle.nesje@xxxxxxxxx.xxx,atte.korhola@xxxxxxxxx.xxx,Keith.Barber@xxxxxxxxx.xxx,Sandy.Tudhope@xxxxxxxxx.xxx ,eavaganov@xxxxxxxxx.xxx, Eystein Jansen <eystein.jansen@xxxxxxxxx.xxx>, Rick Battarbee <r.battarbee@xxxxxxxxx.xxx>, Tim Osborn <t.osborn@xxxxxxxxx.xxx>, , Jan Esper <esper@xxxxxxxxx.xxx>, brazdil@xxxxxxxxx.xxx, benito@xxxxxxxxx.xxx

Dear Colleagues,

This note is to solicit your possible collaboration in an application to the European
Commission under Framework 6, possibly as one of the partners in IMPRINT. This is an
integrated palaeoclimate/climate modelling project concerned primarily with the Holocene,
but also incorporating specific studies on other interglacial warm periods. AT THIS STAGE
THIS IS A PROVISIONAL ENQUIRY RATHER THAN A DEFINITE REQUEST FOR YOUR INVOLVEMENT.
The project has been some time (years) in gestation and has evolved from other proposals.
An unfinished draft is appended to this message for your information - but we would ask
that you respect its confidentiality , whether or not you are interested in working with
us. Eystein Jansen has agreed to coordinate IMPRINT. We are now refining the initial
submission. I, and Valerie Masson, are nominally fronting WorkPackage 1: concerned with
assembling, reinterpreting, amalgamating and analysing the climate data; a combination of
instrumental, documentary and other indirect, proxy climate information. This Workpackage
will also organise the aggregation of best possible climate forcing proxy evidence, as
means of exploring links with the empirical climate data, but also as input to the
significant effort in climate modelling to be undertaken in other workpackages.
WorkPackage 1 has been divided into a number of sub themes or Tasks and these, along with
the content of all Workpackages, is described in the attached document. Note that this is
very much work in progress at this stage and your comments and input to all parts will be
welcome. We will refine the wider list of collaborating institutes at a later stage.

At this stage we envisage a total budget application of about 17 million Euro with a
nominal share of 5 million for WorkPackage 1. While this is a large sum, I am sure you
will appreciate that when distributed among many partners and stretched over five years it
imposes a severe limitation on the total number of partners that can be feasibly included.
Therefore we have had to conceive of different degrees, or levels, of involvement of the
very many colleagues and institutions that are required to make this project a success.
Thus, we envisage a distinction between a number of full partners, though again with
varying resource allocation depending on specific inputs and requirements (still to be
determined), and a larger number of collaborators. Specific funding will be allocated to
facilitate the involvement of these many other groups, who we see taking part in workshops,
in return for full access to joint data and modelling results. This is the only way that
we see of overcoming the envisaged restriction imposed by the EC on total partner numbers.

We have chosen partners who we hope will be able to furnish expertise in specific research
areas and, hopefully, facilitate data assembly and exchange between members of the wider
communities.
PLEASE NOTE THAT THOSE PEOPLE LISTED IN THE "TO" LINE OF ADDRESSES ARE THOSE TENTATIVELY
EARMARKED TO BE TASK LEADERS WITHIN WORKPACKAGE 1. THOSE LISTED UNDER THE "CC" HEADING ARE
EARMARKED TO be PARTNERS - ORGANISING WORK AND DATA EXCHANGE WITHIN THEIR COMMUNITY. We
have a suggested list of many others who we would hope to involve - but not at full
partner level. Your input to the compleinon of this list will be asked for later. We would
ask that , for now, you do not circulate this provisional proposal .
We realise that many other partners could have been fully justifiably included, but the
need for pragmatism must eventually limit their formal roles. We hope that this reality
will be accepted by those colleagues not included as primary partners and they will still
be willing to collaborate to achieve the wider aims of IMPRINT.

The specific partner roles, as suggested to date, are described in the Workpackage 1
section of the appended IMPRINT document. Would you now please indicate whether or not you
are willing to join this effort, and please feel free to comment on any aspect: of
Workpackage 1 to myself and Valerie; or of the project as a whole to Eystein.

With very best wishes,

Keith

--
Professor Keith Briffa,
Climatic Research Unit
University of East Anglia
Norwich, NR4 7TJ, U.K.

Phone: xxx xxxx xxxx
Fax: xxx xxxx xxxx

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From: Stefan Rahmstorf <regentage@xxxxxxxxx.xxx>
To: Eystein Jansen <eystein.jansen@xxxxxxxxx.xxx>
Subject: [Wg1-ar4-ch06] Ch6-Climate Sensitivity
Date: Fri, 01 Oct 2004 11:49:05 +0200
Reply-to: stefan@xxxxxxxxx.xxx
Cc: wg1-ar4-ch06@xxxxxxxxx.xxx

Hi co-authors,
here are some thoughts on what to say on climate sensitivity in our chapter - this is an
attempt to focus on the main, simple messages for policy makers. (I think we should try
retaining those important messages and not lose sight of them amidst all the details,
complexity and caveats.)
The main policy-relevant question could be phrased as follows: Does the past climate
history tell us how sensitive the climate system is to CO2?
I submit that the answers to this we get from different time periods are the following.
Deep Time:
Reconstructions are too uncertain (and boundary conditions too different, e.g. continents
in different places, different ocean circulation) to draw quantitative conclusions about
sensitivity to CO2, but there is clear evidence that times of high CO2 in Earth history
tend to be ice free (Royer et al. 2004). A second piece of evidence is the Late Paleocene
Thermal Maximum, which shows that the climate has responded by warming to a large carbon
release into the atmosphere. Just how large this carbon release was is not known, since
several origins of the carbon are possible, which have different isotope signature and
would thus imply different amounts. But the temperature response was large (6K), and if
anything this response would point to a high sensitivity.
Glacial-Interglacial Changes:
We have by now sufficiently good quantitative reconstructions of CO2 and other forcings as
well as temperatures in order to derive useful quantitative estimates of climate
sensitivity. LGM was the most recent time in history in which CO2 concentration differed
greatly from pre-industrial values, by as much as it does now. It is the closest test case
for response to CO2 changes that we have.
There are two basic methods to derive climate sensitivity:
(i) Based on data analysis - e.g. Lorius et al. 1991 (concluding sensitivity is 3-4 K).
This method has the caveat that this sensitivity applies to colder climate, which may
differ somewhat from that which applies in present climate as the strength of feedbacks is
expected to depend on the mean climate (e.g., stronger snow-albedo feedback in colder
conditions).
(ii) Based on combining data and models - e.g. Schneider von Deimling et al. 2004. Does not
have the above caveat, but depends on models.
Lag of CO2 behind temperature does not imply a lack of CO2 effect on climate, since the lag
is small (centuries, not millennia).
Holocene, last millennium
??
Overall conclusions
Qualitatively, climate history is at least consistent with the accepted CO2 sensitivity.
There is no evidence for much lower or much higher CO2 sensitivity (note that CO2 is not
the only forcing). The more recent climate history (as far back as ice core data go) does
allow quantitative inferences. The results of these estimates all lie within the IPCC range
and provide strong support for this. Paleodata may even allow to reduce this range, since
at least one study argues that values above 4K are very likely inconsistent with the
reconstructed LGM climate: for high CO2 sensitivity, tropical cooling in the glacial should
have been larger.
Cheers,
Stefan
_______________________________________________ Wg1-ar4-ch06 mailing list
Wg1-ar4-ch06@xxxxxxxxx.xxx http://www.joss.ucar.edu/mailman/listinfo/wg1-ar4-ch06

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From: Eystein Jansen <eystein.jansen@xxxxxxxxx.xxx>
To: Keith Briffa <k.briffa@xxxxxxxxx.xxx>, wg1-ar4-ch06@xxxxxxxxx.xxx
Subject: Re: [Wg1-ar4-ch06] IPCC last 2000 years data
Date: Mon, 11 Oct 2004 20:27:35 +0200

<x-flowed>
Hi Keith,
I can take a stab at the THC bit (not strong
evidence so far for linkages to
multidecadal/century scale changes, but cannot be
ruled out) the marine evidence from the North
Atlantic (14C chronological control), and some
aspects of tropical/high latitude linkages.
Eystein

At 17:00 +0xxx xxxx xxxx, Keith Briffa wrote:
>Friends and authors ( especially Ricardo, Olga,
>Fortunat, David, Ramesh, Zhang, Dan, Eystein and
>Valerie)
>Now back from travels (until Wednesday when off to Austria for a few days)
>I thought it best to suggest a break down for
>the writing of the data section for the last
>2000 years of the IPCC palaeoclimate chapter.
>Please see the outline produced at the meeting.
>We have 4 IPCC pages . I will write a short
>intro linking to the instrumental data with
>links to Chapters 3-5. I will coach this in a
>general introduction to this section that
>addresses the points listed in the initial notes
>( namely how we use the various high , and few
>low, resolution data to construct regional and
>large-scale temperature variability , and where
>possible, gain insight into hydrologic
>variability. I will say we use models to get
>insight into methodology and to explore regional
>coverage and seasonality issues and we use
>control and forced model runs to look at
>sensitivity and detection issues , but also use
>date to test model variability and sensitivity .
>I can first go at the NH (SH) Spaghetti diagram
>discussion and hopefully you will pick up the
>regional aspects of the temperature and
>precipitation (moisture) variability .
>Rather than me say - I would like you to come
>back with the major areas you will cover , but
>these may best be done in terms of
>climatologically meaningful regions - ie
>relating to the ENSO, NAM, PDO , AAO, monsoon
>areas - then we could fill in the remaining
>regions if significant non overlap in areas is
>apparent (Eurasia, non-monsoon china etc) . We
>do not want a list of every paper ever written ,
>but a selection of (the better) work that you
>feel has regional relevance (and some length
>presumably). THe other alternative is just to
>divide up the world to our own regions and then
>discuss the climate indices separately. This
>would likely be easier to do . Let me know what
>you think. Either way , we also should have a
>specific discussion of forcings at high
>resolution , and Fortunat, Valerie could cover
>solar and volcanic , perhaps Eystein discussing
>what evidence there is for THC change . The
>knotty issue of THC versus NAO and the link to
>model theories/models could go here - or
>perhaps later in the section 6.4.3.2 ? Davis
>what say you about this? The same is true of
>ENSO links to terrestrial precipitation patterns
>and temperature?
>I don't like the idea of dealing wit quasi
>periodicities separately , but rather wit the
>regional discussions eg North American drought.
>The question of LIA , MWP will come up in the
>large scale average discussion but you can also
>address it in the regional discussions , but in
>a critical and quantitative way. I would like to
>see the evidence for extremmes/abrupt change
>from the regional syntheses and then see if we
>have enough to define and discuss the issue
>separately. Olga could you pick up on the
>glacial variations (perhaps with links to models
>also?)
>
>So come back to me asap to let me know
>impressions and regional/variable focus you all
>wish to pick up. Ricardo will obviously do North
>South linkages as per the PEP1 transect , but
>what about along PEP2 and 3/ WE may have to pick
>this up in the light of the regional data. Can
>you also let me know if/who you might be asking
>to help with writing . Peck , I would still
>rather have Mike Mann in , so what is the story
>here - can I ask him? Suggestions for summary
>Figures still welcome - I would like to have a
>High lat , mid lat , low lat transect type
>figure for temperature , possibly along each PEP
>transect - with longest instrumental data . A
>forcing diagram is also a must - but could
>combine Holocene and "blow up " last 2000 years.
>
>Best wishes
>Keith
>
>--
>Professor Keith Briffa,
>Climatic Research Unit
>University of East Anglia
>Norwich, NR4 7TJ, U.K.
>
>Phone: xxx xxxx xxxx
>Fax: xxx xxxx xxxx
>
>http://www.cru.uea.ac.uk/cru/people/briffa/
>_______________________________________________
>Wg1-ar4-ch06 mailing list
>Wg1-ar4-ch06@xxxxxxxxx.xxx
>http://www.joss.ucar.edu/mailman/listinfo/wg1-ar4-ch06

--
______________________________________________________________
Eystein Jansen
Professor/Director
Bjerknes Centre for Climate Research and
Dep. of Earth Science, Univ. of Bergen
All

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From: Jonathan Overpeck <jto@u.arizona.edu>
To: "Ricardo Villalba" <ricardo@xxxxxxxxx.xxx>
Subject: Re: [Wg1-ar4-ch06] Fw: Section on Modes of Variability
Date: Thu, 16 Dec 2004 17:37:xxx xxxx xxxx
Cc: k.briffa@xxxxxxxxx.xxx, peltier@xxxxxxxxx.xxx, Eystein Jansen <eystein.jansen@xxxxxxxxx.xxx>

Hi Ricardo - good to hear from you. Thanks too for the interesting figure. I have some
comments on this section (6.5.4) and also for the others' you're helping to lead.

Regarding 6.5.4 - I hope Dick and Keith will have jump in to help you lead, and I can too.
I think the hardest, yet most important part, is to boil the section down to 0.5 pages. In
looking over your good outline, sent back on Oct. 17 (my delay is due to fatherdom just
after this time), you cover ALOT. The trick may be to decide on the main message and use
that to guid what's included and what is left out. For the IPCC, we need to know what is
relevant and useful for assessing recent and future climate change. Moreover, we have to
have solid data - not inconclusive information. My take:

ENSO - coral records sensitive to ENSO (e.g., Urban et al. and Cobb et al - attached)
suggest ENSO has changed in response to past forcing change (Cobb et al - updated interp by
mann et al - see recent email attachment) and recent climate change (Urban et al). Ditto
for Indian Ocean - not sure if can connect to dipole - I could ask Julie Cole? NAO - lots
of papers and what's the consensus? I'm not sure, but I think it is that we can't say for
sure what has happend to the NAO - or AO for sure (Keith might no more - recent Ed Cook
paper might be the key? - I'm not an expert here). Same thing for PDO (not an expert, but
aren't their recons that don't agree - see cole et al for one- attached). In both these
cases, the recons don't always agree. Or do they say the NAO variability has stayed pretty
constant?

Tropical Atlantic - Black et al 1999 (attached to prev email) also says 12year mode (no
consensus if diapole is the correct name for what Chang first described - see ref in Black
attached) has been constant for 800 years.

Annual modes - does paleo have anything definitive to say yet? I'm a coauthor on a soon to
be submitted AO recon paper, but I'm not sure reviewers will go for it - nor does it match
D'Arrigo's recent AO recon paper (can't find).

So, the trick is for you to lead us (Dick, Keith, me - maybe Julie - ENSO expert) to
produce 0.5 pages of HIGHLY focused and relevant stuff. Can you take another crack at your
outline and then tell us what you need? Thanks!

Regarding 6.5.9 - can you help Dan, Ramesh and others to make quick headway on this one -
it's totally missing. Thanks!

Regarding 6.3.2.1 - Keith will need help, no doubt - particularly with a good S. Hemisphere
perspective (he can override me on this, but since I'm contacting you...) thanks! What do
we have for the southern hem? Southern S. America, New Zealand, Tasmania, ice core?

Regarding 6.3.2.2 - what's your opinion of where this section stands?

Thanks - hope you are enjoying summer - although Tucson never gets that cold!

Best, Peck

----- Original Message -----

From: [1]Ricardo Villalba

To:

Sent: Thursday, December 16, 2004 2:55 PM

Subject: Fw: Section on Modes of Variability

Dear IPCC colleagues

Please, find attached a preliminary draft of the proposed figure for the section: Modes
of variability. The caption follows. Best regards,

Modes of variability

Figure caption. Coherent modes of climate variability across the Pacific Ocean during
the past four centuries. The upper part of this figure compare temperature-sensitive
tree-ring records (red triangles) from high-latitude, Western North and South America
with a geochemical coral record (yellow triangle) from Raratonga, tropical South
Pacific. The series shown from top to bottom are: Spring/Summer Gulf of Alaska
temperature reconstruction (1xxx xxxx xxxx; Wiles et al., 1998), Sr/Ca coral record from
Rarotonga (1xxx xxxx xxxx; Linsley et al. 2004) and annual Northern Patagonia temperature
reconstruction (1xxx xxxx xxxx; Villalba et al., 2003). Correlation coefficients between
records are indicated. To facilitate the comparison, the Sr/Ca coral record is shown
reversed.

Interdecadal to centennial variability in each time series was isolated by using
singular spectrum analysis (SSA; lower part of the figure). For each record, all SSA
reconstructed components with mean frequencies longer than 20 years where summed.
Correlation coefficients between these long-term modes of variability are also shown.
Thin and thick arrows indicate coincidences in oscillations between the Raratonga and
one or two high-latitude records, respectively.

Linsley, B., G. Wellington, D. Schrag, L. Ren, M. Salinger and A. Tudhope, 2004:
Geochemical evidence from corals for changes in the amplitude and spatial pattern of
South Pacific interdecadal climate variability over the last 300 years. Climate
Dynamics, 22, 1-11.

Villalba, R., Lara, A., Boninsegna, J.A., Masiokas, M., Delgado, S., Aravena, J.C.,
Roig, F.A., Schmelter, A., Wolodarsky, A., Ripalta, A. 2003. Large-scale temperature
changes across the southern Andes: 20th-century variations in the context of the past
400 years. Climatic Change, 59: xxx xxxx xxxx.

Wiles, G. C., D'Arrigo, R.D. and Jacoby, G.C., 1998. Gulf of Alaska atmosphere-ocean
variability over recent centuries inferred from coastal tree-ring records. Climatic
Change, 38, xxx xxxx xxxx.

Ricardo

Ricardo Villalba
Departamento de Dendrocronologa
e Historia Ambiental
IANIGLA - CRICYT
C.C. 330, (5500) Mendoza, Argentina
Tel: +54 (2xxx xxxx xxxxext. 48
Fax: +54 (2xxx xxxx xxxx
e-mail: [2]ricardo@xxxxxxxxx.xxx
PAGES SSC: [3]http://www.pages.unibe.ch/

Attachment converted: Macintosh HD:modes of variation.jpg (JPEG/prvw) (000C0BD1)
_______________________________________________
Wg1-ar4-ch06 mailing list
Wg1-ar4-ch06@xxxxxxxxx.xxx
http://www.joss.ucar.edu/mailman/listinfo/wg1-ar4-ch06

--

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: xxx xxxx xxxx
fax: xxx xxxx xxxx
http://www.geo.arizona.edu/
http://www.ispe.arizona.edu/

Attachment Converted: "c:eudoraattachCobb2003Nature.pdf" Attachment Converted:
"c:eudoraattachCooketal2002GRL.pdf" Attachment Converted:
"c:eudoraattachUrbanetal00.nature.pdf" Attachment Converted:
"c:eudoraattachColeetal2002GRL.pdf"

References

1. mailto:ricardo@xxxxxxxxx.xxx
2. mailto:ricardo@xxxxxxxxx.xxx
3. http://www.pages.unibe.ch/

Original Filename: 1103828684.txt | Return to the index page | Permalink | Later Emails

From: "Michael E. Mann" <mann@xxxxxxxxx.xxx>
To: Keith Briffa <k.briffa@xxxxxxxxx.xxx>
Subject: Re: Fwd: Re: [Wg1-ar4-ch06] IPCC last 2000 years data
Date: Thu, 23 Dec 2004 14:04:xxx xxxx xxxx

Hey Keith,
I hope your visit w/ your family went well...
I went ahead and tried to make some constructive comments on what you sent (figured it
would be nice to get this out of the way before the holidays come round)..
Let me say I think it's shaping up very nicely--looks like it should be a significant
improvement on the '01 report. You've handled the various controversies and points of
dispute delicately and adeptly, while still driving home in the end the key point (that the
evidence appears to point to anomalous late 20th century behavior).
I made a dozen or so minor comments--please make use of them as you see fit.
Lets reconvene on this after the holidays. Thanks again for including me in and giving me
an opportunity to comment.
I hope the rest of your holidays go well,
mike
At 01:31 PM 12/22/2004, you wrote:

Mike
don't know what the status of the whole chapter is - but I thought I would send this
very first and rough
draft to you anyway - I have to wait and see the whole thing and hear from Peck before
doing more.
Just heard my dad is now pretty much bedridden and officially declared blind (diabetes
etc) and have to fit in a visit to him and mum (who I have not seen for ages) and spend
at least a few days with the kids so there is no way I can work more on this till later
- as I said - really appreciate your input , have a great Christmas and for f..ks sake
keep the right priorities to the fore as the years progress
cheers
Keith

Date: Wed, 22 Dec 2004 18:23:02 +0000
To: Jonathan Overpeck <jto@u.arizona.edu>
From: Keith Briffa <k.briffa@xxxxxxxxx.xxx>
Subject: Re: [Wg1-ar4-ch06] IPCC last 2000 years data
Cc: Eystein Jansen <eystein.jansen@xxxxxxxxx.xxx>
Bcc: t.m.melvin@xxxxxxxxx.xxx,Tim Osborn <t.osborn@xxxxxxxxx.xxx>
Peck and Eystein
I have to break off now for the christmas period
This is unavoidable. I am sending what I have now
even though I am not at all happy with it.
It is obviously only part way there. Getting the data
to produce Figures and work out how to design them
is going to be time very consuming
and I will rely entirely on Tim here to do them
- and the regional input
stuff if wanted will need input from a number of people
that I have not been able to contact (see later)
The borehole discussion (contributed to by Henry Pollack) will need
batting around and Henry (and Mike , who contributed
a section on regional forced changes) will need to be kept
on board. There will be loads to say on the simulated
temperature histories and Tim will help here also
- but much is unpublished or
even unanalysed (hence Simon and Eduardo will need
to contribute eventually). The glacier bit at the end is what
Olga sent and I have not had time to work through it.
You two need to give some direction as to how
much you wish to have explicitly looking at the mass of
NAO?AO reconstructions , ditto ENSO or PDO and all the
simulations of these - but at this stage not sure where in overall
plan all this going. Do we really want a discussion on MWP
and LIA per se ? The regional descriptions , including Southern Hemisphere
could be infinite length and I suppose we should only discuss longest or
pre assimilated information - but will need specific input here from colleagues
if we are to do these regional (including precipitation ) sections .
I know Julie and Ed , and presumably Eystein , will be the best people to ask.
I am attaching the current text and placeholder ideas for Figures .
Not feasible to work more on these until know wider priorities re space.
Have had bad experience with ENDNOTE - and Tom Melvin here will forward
the biblio file later.
I wanted to do more , but that is all I can manage til after Xmas
Here is wishing you (and your loved ones) all the best
Keith
Professor Keith Briffa,
Climatic Research Unit
University of East Anglia
Norwich, NR4 7TJ, U.K.
Phone: xxx xxxx xxxx
Fax: xxx xxxx xxxx

--
Professor Keith Briffa,
Climatic Research Unit
University of East Anglia
Norwich, NR4 7TJ, U.K.
Phone: xxx xxxx xxxx
Fax: xxx xxxx xxxx
[1]http://www.cru.uea.ac.uk/cru/people/briffa/

______________________________________________________________
Professor Michael E. Mann
Department of Environmental Sciences, Clark Hall
University of Virginia
Charlottesville, VA 22903
_______________________________________________________________________
e-mail: mann@xxxxxxxxx.xxx Phone: (4xxx xxxx xxxxFAX: (4xxx xxxx xxxx
[2]http://www.evsc.virginia.edu/faculty/people/mann.shtml
Attachment Converted: "c:eudoraattachIPCCFAR_xxx xxxx xxxx_ memxxx xxxx xxxx.doc"

References

1. http://www.cru.uea.ac.uk/cru/people/briffa/
2. http://www.evsc.virginia.edu/faculty/people/mann.shtml

Original Filename: 1104893567.txt | Return to the index page | Permalink | Later Emails

From: Jonathan Overpeck <jto@u.arizona.edu>
To: k.briffa@xxxxxxxxx.xxx
Subject: Fwd: Re: [Wg1-ar4-ch06] IPCC last 2000 years data
Date: Tue, 4 Jan 2005 21:52:xxx xxxx xxxx
Cc: Eystein Jansen <eystein.jansen@xxxxxxxxx.xxx>, cddhr@xxxxxxxxx.xxx

Hi Keith - Happy new year. Hopefully, you had a good holiday. I've had a chance to read
your section and hopefully you've had a chance to read what I sent just before the
holidays. The purpose of this email is to help get a focus on the finish line (just a few
days away) and to get a dialog going that will hopefully help you finish section 6.3.2.1.
If you'd like to talk on the phone, just let me know.

Please see my email from right before xmas holidays for original comments. Plus, here are
the new ones from both me and David Rind:

0) as leader of this KEY section, we need you to take the lead integrating everything you
think should be integrated, editing and boiling it down to just ca 4 pages of final text
(e.g., 8 pages of typed text plus figs). This means cutting some material (e.g., forcings
and simulations) and perhaps moving glacier record (MUCH boiled down) to a box. See below.
00) note that we can also perhaps move some of the details to the appendix (although we
won't write this until after the current ZOD crunch, save an outline of what you might want
in there).
1) I like your figure ideas, with the comments:
1a) I don't think you need figure 1d - the SH recons are sketchy since not much data, and
it might be better to just discuss in a sentence or three. Any space saved is good too. Not
sure about your proposed 1e - have to see it, I guess.
1b) Figure 2 looks interesting. I'm trying to get the latest Arctic recon from Konrad
Hughen - it is quite robust and a significant multi-proxy update. Should be published in
time, though not sure thing since he's still hot on including his (our) AO recon which is
more sketchy
1c) I think we can save space and improve organization if we DO NOT include Fig 3. However,
this is open for debate - see David's comments below.
2) I agree with David's comments in general - so see them below. The prickly issue is where
to put the forcings and simulated changes. I am close to having the prose from the
radiation chapter, including the latest Lean and Co's view on solar - this will make many
of the existing simulations involving inferred past solar forcing suspect (I will send in a
day or so I hope). This means that we might be best saving space and downplaying this work
some. I'm not sure, but wanted to debate it with you. Also, Chap 9 will have simulations in
spades, so we can save space by letting them do it. Also, as David points out, we can focus
on it elsewhere in our chapter more concisely - leaving you to focus on the VERY important
obs record of temp and other changes. Can you tell, I'm still not 100% sure? I'll send
another email to you and others about this in a bit.
3) Your section is too long and needs to be condensed. Thus, you need to think through
what's most important and what's less so. For example, we need to figure out how to
condense the glacier record of change. David thinks it should be a separate section that
cuts across time scales (i.e., Holocene and last 2000 years). Perhaps we should try to make
it into a box - 3 to 5 short paragraphs and a figure or two. Either way we have to really
wack it. What do you think - you and I should be on the same page with Eystein before
discussing w/ Olga perhaps. Or you can discuss with her - you're the lead on this section.
4) you're doing an impressive job! Lots to keep track of.
Next, here is what David has offered. Take it all with a grain of salt, but I have read it
and he has many good points. On the structural or any other points, I'm happy to discuss on
the phone, or you can just debate with him and me on email.
******* From David Rind 1/4/05 ****************
6.3 Understanding Past Climate System Change (forcing and response)
6.3.1 Introduction (0.5 pages)
6.3.2 The Current Interglacial
6.3.2.1 Last 2000 years (4 pages)
Figure 1 should be of the last 2000 years, with appropriate caveats, not just since 1860
(which will undoubtedly be in other chapters).

pp. 8-18: The biggest problem with what appears here is in the handling of the greater
variability found in some reconstructions, and the whole discussion of the 'hockey stick'.
The tone is defensive, and worse, it both minimizes and avoids the problems. We should
clearly say (e.g., page 12 middle paragraph) that there are substantial uncertainties that
remain concerning the degree of variability - warming prior to 12K BP, and cooling during
the LIA, due primarily to the use of paleo-indicators of uncertain applicability, and the
lack of global (especially tropical) data. Attempting to avoid such statements will just
cause more problems.
In addition, some of the comments are probably wrong - the warm-season bias (p.12) should
if anything produce less variability, since warm seasons (at least in GCMs) feature smaller
climate changes than cold seasons. The discussion of uncertainties in tree ring
reconstructions should be direct, not referred to other references - it's important for
this document. How the long-term growth is factored in/out should be mentioned as a prime
problem. The lack of tropical data - a few corals prior to 1700 - has got to be discussed.
The primary criticism of McIntyre and McKitrick, which has gotten a lot of play on the
Internet, is that Mann et al. transformed each tree ring prior to calculating PCs by
subtracting the 1xxx xxxx xxxxmean, rather than using the length of the full time series (e.g.,
1xxx xxxx xxxx), as is generally done. M&M claim that when they used that procedure with a red
noise spectrum, it always resulted in a 'hockey stick'. Is this true? If so, it constitutes
a devastating criticism of the approach; if not, it should be refuted. While IPCC cannot be
expected to respond to every criticism a priori, this one has gotten such publicity it
would be foolhardy to avoid it.
In addition, there are other valid criticisms to the PC approach. Assuming that the PC
structure stays the same was acknowledged in the Mann et al paper as somewhat risky, given
the possibility of altered climate forcing (e.g., solar). Attempting to reconstruct
tropical temperatures using high latitude PCs assumes that the PCs are influenced only by
global scale processes. In a paper we now have in review in JGR, and in other papers
already published, it is shown that high latitude climate changes can directly affect the
local expression of the modes of variability (NAO in particular). So attempting to fill in
data at other locations from PCs that could have local influences may not work well; at the
least, it has large uncertainties associated with it.
The section from p.xxx xxxx xxxxsimulations of temperature change over the last millennium ,
including regional expressions - should not be in this section. It is covered in the
modeling section (several different times), and will undoubtedly be in other chapters as
well. And the first paragraph on p. 19 is not right - only by using different forcings have
models been able to get similar responses (which does not constitute good agreement). The
discussion in the first paragraph of p. 20 is not right - the dynamic response is almost
entirely in winter, which would not have affected the 'warm season bias'
paleoreconstructions used to prove it. It also conflicts with ocean data (Gerard Bond,
personal communication). Anyway, it's part of the section that should be dropped.
pp. 20-28: The glacial variations should be summarized in a coherentglobal picture.
Variations as a function of time should be noted - not just lumped together between 1400
and 1850 - for example, it should be noted where glaciers advanced during the 17th century
and retreated during the 19th century, for that is important in understanding possible
causes for the Little Ice Age (as well as the validity of the 'hockey stick'). The
discussion on the bottom of p.xxx xxxx xxxxas to the causes of the variations is inappropriate
and should be dropped - note if solar forcing is suspect, every paragraph that relates
observed changes to solar forcing will be equally suspect (e.g., see also p. 44, first
paragraph).
Bottom of p. 27: Greene et al. (GRL, 26, 1xxx xxxx xxxx, 1999) did an analysis of 52 glaciated
areas from 30-60N and found that the highest correlation between their ELA variations in
the last 40 years was with summer season freezing height and winter season precip. The warm
season freezing height was by far more important. Therefore, the relationship of glacier
variations to NAO changes (which are important only in winter), as discussed in this
paragraph, while perhaps valid for a period of time in southern Norway, is not generally
applicable.

p. xxx xxxx xxxxon forcings: note that this is redundant to what is discussed in several later
sections (e.g., 6.5.2); and other chapters), and that is true of forcing in general for the
whole of section 6.2. I would strongly suggest dropping forcing from section 6.3.2.1, at
least, and perhaps giving it its own number, or referring to othersubsections for it. It
has a different flavor from the responses, and the section is already very big. Forcing
does need to be discussed in the paleoclimate chapter, for reasons of climate sensitivity
and explaining observations, but that is what Chapter 6.5 is about.
(In summary - 6.3.2.1 already is taking on one controversy - paleotemperatures, which is
needs to do better, It should not have to deal with the forcing problems as well, and
especially not in an off-handed way.)
Specific comments: p. 36: 6 ppm corresponds to a temperature response of 0.3 to 0.6

Original Filename: 1104941753.txt | Return to the index page | Permalink | Later Emails

From: Jonathan Overpeck <jto@u.arizona.edu>
To: Keith Briffa <k.briffa@xxxxxxxxx.xxx>
Subject: Fwd: Re: the Arctic paper and IPCC
Date: Wed, 5 Jan 2005 11:15:xxx xxxx xxxx
Cc: Eystein Jansen <eystein.jansen@xxxxxxxxx.xxx>

<x-flowed>
Hi Keith - great (!) to hear from you - hope you had a good holiday.
Your reward (ha) is the attached paper and comment below from Konrad.
He can supply data if needed for a synthetic figure, but we can add
this later once the Science paper he mentions (w/ us a co-authors
among millions, I assume) gets vetted more. Your call.

I'm still not convinced about the AO recon, and am worried about the
late 20th century "coolness" in the proxy recon that's not in the
instrumental, but it's a nice piece of work in any case.

Now, for all the issues you raise on other stuff in your email, I'll
address to you and that crowd.

thanks, Peck

>X-Sieve: CMU Sieve 2.2
>Date: Wed, 05 Jan 2005 10:53:xxx xxxx xxxx
>From: Konrad Hughen <khughen@xxxxxxxxx.xxx>
>Organization: WHOI
>X-Accept-Language: en-us, en
>To: Jonathan Overpeck <jto@u.arizona.edu>
>Subject: Re: the Arctic paper and IPCC
>X-Virus-Status: No
>X-Virus-Scanned: by amavisd-new at email.arizona.edu
>
>Hey Peck,
>
>Here's a pdf of a draft of Peter's methods paper. The figures will
>be what goes into the Science paper. I've sent the whole thing to
>help explain the figs, but let me know if you guys have questions.
>Also, I have a movie of reconstructed Arctic temp through time. Too
>big to attach but I'll try and get it to you somehow. Pretty cool.
>We're planning to include the movie and supplemental figs
>("robustness" tests, etc.) into the new website Matt's working on.
>
>Good to talk yesterday. I'll get a CV to you today.
>
>-Konrad
>

--
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: xxx xxxx xxxx
fax: xxx xxxx xxxx
http://www.geo.arizona.edu/
http://www.ispe.arizona.edu/
</x-flowed>

Attachment Converted: "c:eudoraattachArcticOct16.pdf"

Original Filename: 1104945887.txt | Return to the index page | Permalink | Later Emails

From: Jonathan Overpeck <jto@u.arizona.edu>
To: Keith Briffa <k.briffa@xxxxxxxxx.xxx>
Subject: Re: Fwd: Re: [Wg1-ar4-ch06] IPCC last 2000 years data
Date: Wed, 5 Jan 2005 12:24:xxx xxxx xxxx
Cc: Eystein Jansen <eystein.jansen@xxxxxxxxx.xxx>, cddhr@xxxxxxxxx.xxx, Fortunat Joos <joos@xxxxxxxxx.xxx>, joos <joos@xxxxxxxxx.xxx>, "Ricardo Villalba" <ricardo@xxxxxxxxx.xxx>

<x-flowed>
Hi Keith and Co - I think David likes a good debates, so the main
thing is to consider his comments and respond appropriately. Although
the first priority has to be on the ZOD text and display items, maybe
you can go back over his comments AFTER the looming deadline and
further discuss things with David and others. For now, just work away.

The biggest issue is how to handle forcing and simulations - i.e.,
where to put different pieces in the chapter. Eystein and I will help
the team work through this. More soon, but for now just proceed as
you have been proceeding. There is real merit to the concept that
your section is about how climate varied over the last 2ka, and what
caused these variations. The flip side is that we need to get a clear
vision of how this differs from what goes into the other sections.
Eystein and I will work more on this asap.

Your plan re: glaciers is good. That's a tough one, but it has to be
boiled WAY down. Moreover, my gut is to focus on the extent to which
these complicated natural archives (e.g., complicated by ppt change)
support or do not support the other proxy evidence/conclusions. This
is why I was thinking we might think about a box, and to include the
Lonnie perspective in it - e.g., glaciers are now melting everywhere
(almost - we know why they are not in those places) in a manner
unprecedented in the last xxxx years. Make sense? See what Olga says,
and if needbe, I can help focus that stuff more.

Thanks! Peck

>Hi Peck (et al)
>I am considering comments (including David's) re last 2000 years -
>some are valid = some are not . Will try to chop out bits but we
>need this consensus re the forcing and responses bit - I am for
>keeping the forcings in as much as they relate to the specific model
>runs done - and results for last 1000 years as I suspect that they
>will not be covered in the same way elsewhere . David makes couple
>good points - but extent to which forcings different (or
>implementation) perhaps need addressing here. The basic agreement I
>mean is that the recent warming is generally unprecedented in these
>simulations.
>It will take time and input from the tropical ice core /coral people
>to do the regional stuff well . I think the glaciological stuff is a
>real problem - other than just showing recent glacial states (also
>covered elsewhere) - of course difficult to interpret any past
>records without modelling responses (as in borehole data), but this
>requires considerable space . My executive decision would be to ask
>Olga to try to write a couple of papragraphs on limits of
>interpretation for inferring precisely timed global temperature
>changes? What do others think? I only heaved Olga's stuff in at
>last moment rather than not include it - but of course it needs
>considerable shortening. The discussion of tree-ring stuff is
>problematic because it requires papers to be published eg direct
>criticism of Esper et al. We surely do not want to waste space HERE
>going into this esoteric topic? All points on seasonality , I agree
>with , but the explicit stuff on M+M re hockey stick - where is
>this? ie the bit about normalisation base affecting redness in
>reconstructions - sounds nonsense to me ?
>
>I have to consider the comments in detail but am happy for hard
>direction re space and focus. If concensus is no forcings and model
>results here fine with me - Peck and Eystein to rule
>Keith
>

--
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: xxx xxxx xxxx
fax: xxx xxxx xxxx
http://www.geo.arizona.edu/
http://www.ispe.arizona.edu/
</x-flowed>

Original Filename: 1105024270.txt | Return to the index page | Permalink | Later Emails

From: Keith Briffa <k.briffa@xxxxxxxxx.xxx>
To: solomina@xxxxxxxxx.xxx
Subject: Fwd: Re: Fwd: Re: [Wg1-ar4-ch06] IPCC last 2000 years data
Date: Thu Jan 6 10:11:xxx xxxx xxxx
Cc: jto@u.arizona.edu,Eystein Jansen <eystein.jansen@xxxxxxxxx.xxx>

Olga
am sending this to get you in this loop re the discussion for slimming down the 2000 year
section Basically , IN THIS BIT - the decision is to reduce the glacier evidence to a very
much smaller piece , coached in the sense of how the glacier evidence is problematic for
interpreting precise and quantitative indications of the extent of regional or Hemispheric
Warmth (and even cold) - issues of translating tongue position or volume into specific
temperature and precipitation forcing . Hence , I am having to remove the stuff you sent
and am asking if you could consider trying to write a brief section dealing with the issues
I raise ? I also attach some initial comments by David Rind (on the full first draft of the
chapter sent round by Eystein) for consideration Sorry about this - but presumable (as you
suggested earlier) some of this can go in the 10K bit. You can shout at me (and the others)
later!
cheers
Keith

X-Sender: jto@xxxxxxxxx.xxx
Date: Wed, 5 Jan 2005 12:24:xxx xxxx xxxx
To: Keith Briffa <k.briffa@xxxxxxxxx.xxx>
From: Jonathan Overpeck <jto@u.arizona.edu>
Subject: Re: Fwd: Re: [Wg1-ar4-ch06] IPCC last 2000 years data
Cc: Eystein Jansen <eystein.jansen@xxxxxxxxx.xxx>, cddhr@xxxxxxxxx.xxx,
Fortunat Joos <joos@xxxxxxxxx.xxx>, joos <joos@xxxxxxxxx.xxx>,
"Ricardo Villalba" <ricardo@xxxxxxxxx.xxx>
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Hi Keith and Co - I think David likes a good debates, so the main thing is to consider
his comments and respond appropriately. Although the first priority has to be on the ZOD
text and display items, maybe you can go back over his comments AFTER the looming
deadline and further discuss things with David and others. For now, just work away.
The biggest issue is how to handle forcing and simulations - i.e., where to put
different pieces in the chapter. Eystein and I will help the team work through this.
More soon, but for now just proceed as you have been proceeding. There is real merit to
the concept that your section is about how climate varied over the last 2ka, and what
caused these variations. The flip side is that we need to get a clear vision of how this
differs from what goes into the other sections. Eystein and I will work more on this
asap.
Your plan re: glaciers is good. That's a tough one, but it has to be boiled WAY down.
Moreover, my gut is to focus on the extent to which these complicated natural archives
(e.g., complicated by ppt change) support or do not support the other proxy
evidence/conclusions. This is why I was thinking we might think about a box, and to
include the Lonnie perspective in it - e.g., glaciers are now melting everywhere (almost
- we know why they are not in those places) in a manner unprecedented in the last xxxx
years. Make sense? See what Olga says, and if needbe, I can help focus that stuff more.
Thanks! Peck

Hi Peck (et al)
I am considering comments (including David's) re last 2000 years - some are valid =
some are not . Will try to chop out bits but we need this consensus re the forcing and
responses bit - I am for keeping the forcings in as much as they relate to the specific
model runs done - and results for last 1000 years as I suspect that they will not be
covered in the same way elsewhere . David makes couple good points - but extent to which
forcings different (or implementation) perhaps need addressing here. The basic agreement
I mean is that the recent warming is generally unprecedented in these simulations.
It will take time and input from the tropical ice core /coral people to do the regional
stuff well . I think the glaciological stuff is a real problem - other than just showing
recent glacial states (also covered elsewhere) - of course difficult to interpret any
past records without modelling responses (as in borehole data), but this requires
considerable space . My executive decision would be to ask Olga to try to write a couple
of papragraphs on limits of interpretation for inferring precisely timed global
temperature changes? What do others think? I only heaved Olga's stuff in at last moment
rather than not include it - but of course it needs considerable shortening. The
discussion of tree-ring stuff is problematic because it requires papers to be published
eg direct criticism of Esper et al. We surely do not want to waste space HERE going into
this esoteric topic? All points on seasonality , I agree with , but the explicit stuff
on M+M re hockey stick - where is this? ie the bit about normalisation base affecting
redness in reconstructions - sounds nonsense to me ?
I have to consider the comments in detail but am happy for hard direction re space and
focus. If concensus is no forcings and model results here fine with me - Peck and
Eystein to rule
Keith

--
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: xxx xxxx xxxx
fax: xxx xxxx xxxx
[1]http://www.geo.arizona.edu/
[2]http://www.ispe.arizona.edu/

--
Professor Keith Briffa,
Climatic Research Unit
University of East Anglia
Norwich, NR4 7TJ, U.K.

Phone: xxx xxxx xxxx
Fax: xxx xxxx xxxx
[3]http://www.cru.uea.ac.uk/cru/people/briffa/

References

1. http://www.geo.arizona.edu/
2. http://www.ispe.arizona.edu/
3. http://www.cru.uea.ac.uk/cru/people/briffa/

Original Filename: 1105282939.txt | Return to the index page | Permalink | Later Emails

From: "olgasolomina" <olgasolomina@xxxxxxxxx.xxx>
To: k.briffa@xxxxxxxxx.xxx
Subject: IPCC glaciers
Date: Sun, 9 Jan 2005 10:02:19 +0300 (MSK)
Reply-to: olgasolomina@xxxxxxxxx.xxx
Cc: jto@u.arizona.edu, eystein.jansen@xxxxxxxxx.xxx, Valerie.Masson@xxxxxxxxx.xxx, ricardo@xxxxxxxxx.xxx

Hi Keith,

May I have your part of the text (2ka) to have a look, please. As far as I understand we decided to have glacier fluctuations separately in a frame. In this case, shall we keep glacier variations in the Holocene or we will extract it to place in this frame? I will contact Georg Kaser (ch 04)to see what they already have to comment on glacier/climate links. They must have treated this problem already. Besides it is more natural to concider it using the instrumental data. In this case we will deal with the paleo problem only, i.e. the dating of moraines, the errased traces of old advances, the use of lacustrine deposits to reconstruct the glacier erosion (size), the reconstruction of former ELAs, the sizes of retreated glacier etc. Shall we discuss the accumulation reconstructed from the ice cores or it will be just the problem of glacier front variations?
Another possibility is to have a common frame with the ch 04: How glaciers reflect climate and what they say about the climate in the Holocene (last 2ka).

I need the answers before I begin.

Please notice the change of my e-mail address. I will check both addresses a while, but have to move to a new one olgasolomina@xxxxxxxxx.xxx

Regards,
olga

Original Filename: 1105386027.txt | Return to the index page | Permalink | Later Emails

From: Jonathan Overpeck <jto@u.arizona.edu>
To: Eystein Jansen <eystein.jansen@xxxxxxxxx.xxx>
Subject: Re: [Wg1-ar4-ch06] comments to 6.3.2.1 (mainly for Keith)
Date: Mon, 10 Jan 2005 14:40:xxx xxxx xxxx
Cc: Keith Briffa <k.briffa@xxxxxxxxx.xxx>, cddhr@xxxxxxxxx.xxx, rahmstorf@xxxxxxxxx.xxx, joos <joos@xxxxxxxxx.xxx>

<x-flowed>
I agree; Keith should have the room, and section 6.5.8 should be
compatible - has Fortunat followed the discussion between
David/Stefan. Can you guys (David, Stefan, Keith, and Fortunat)
ensure this?

Thanks, Peck

>Hi,
>interesting discussion on an important topic. If space is the
>limiting factor we may have to evaluate whether to cut back on less
>central issues elswhere in the chapter. We will to a large extent be
>judged on how we tackle the hockey stick, sensitivity, unprecedented
>20th century warming isuues in view of palaeo, and if a slight
>expansion is what it takes to do this properly, then I am
>sympathetic to that (without having heard Peck on the issue).
>Cheers,
>Eystein
>
>
>
>At 16:32 +0xxx xxxx xxxx, Keith Briffa wrote:
>>thanks David
>>have to say that it is very difficult to say much in the minimal
>>space - and we really need a page to discuss the problems in the
>>reconstruction and and interpretation of the various forcings in
>>different models - I am just going to put this down in an over
>>abbreviated way and ask for specific corrections for you and Stefan
>>et al. The detail perhaps depends on what the final Figure looks
>>like and Tim is trying to put it together but lots of weird and
>>interesting stuff / questions arise as we do - especially relating
>>to past estimates of solar irradiance used by different people. At
>>15:29 10/01/2005, David Rind wrote:
>>>(I tried to send this earlier and it got hung up; apologies if it
>>>eventually gets through and you get a second version.)
>>>
>>>Well, yes and no. If the mismatch between suggested forcing, model
>>>sensitivity, and suggested response for the LIA suggests the
>>>forcing is overestimated (in particular the solar forcing), then
>>>it makes an earlier warm period less likely, with little
>>>implication for future warming. If it suggests climate sensitivity
>>>is really much lower, then it says nothing about the earlier warm
>>>period (could still have been driven by solar forcing), but
>>>suggests future warming is overestimated. If however it implies
>>>the reconstructions are underestimating past climate changes, then
>>>it suggests the earlier warm period may well have been warmer than
>>>indicated (driven by variability, if nothing else) while
>>>suggesting future climate changes will be large.
>>>
>>>This is the essence of the problem.
>>>
>>>David
>>>
>>>
>>>
>>>
>>>
>>>At 9:28 AM +0000 1/10/05, Keith Briffa wrote:
>>>>THanks Stefan
>>>>At 21:13 07/01/2005, Stefan Rahmstorf wrote:
>>>>>Keith,
>>>>>
>>>>>some comments added in the text for the past millennium, plus I
>>>>>wrote some extra sentences on the implications of the dispute
>>>>>(repeated below).
>>>>>Hope it is useful,
>>>>>Stefan
>>>>>
>>>>>>Note that the major differences between the proxy
>>>>>>reconstructions and between the model simulations for the past
>>>>>>millennium occur for the cool periods in the 17th-19th
>>>>>>Centuries; none of these reconstructions or models suggests
>>>>>>that there was a warmer period than the late 20th Century in
>>>>>>the record.
>>>>>>
>>>>>>A larger amplitude of preindustrial natural climate variability
>>>>>>does not imply a smaller anthropogenic contribution to 20th
>>>>>>Century warming (which is estimated from 20th Century data, see
>>>>>>Chapter XXX on attribution), nor does it imply a smaller
>>>>>>sensitivity of climate to CO2, or a lesser projected warming
>>>>>>for the future.
>>>>>
>>>>>
>>>>>--
>>>>>Stefan Rahmstorf
>>>>><http://www.ozean-klima.de>www.ozean-klima.de
>>>>>www.realclimate.org
>>>>>_______________________________________________
>>>>>Wg1-ar4-ch06 mailing list
>>>>>Wg1-ar4-ch06@xxxxxxxxx.xxx
>>>>>http://www.joss.ucar.edu/mailman/listinfo/wg1-ar4-ch06
>>>>
>>>>--
>>>>Professor Keith Briffa,
>>>>Climatic Research Unit
>>>>University of East Anglia
>>>>Norwich, NR4 7TJ, U.K.
>>>>
>>>>Phone: xxx xxxx xxxx
>>>>Fax: xxx xxxx xxxx
>>>>
>>>>http://www.cru.uea.ac.uk/cru/people/briffa/
>>>>_______________________________________________
>>>>Wg1-ar4-ch06 mailing list
>>>>Wg1-ar4-ch06@xxxxxxxxx.xxx
>>>>http://www.joss.ucar.edu/mailman/listinfo/wg1-ar4-ch06
>>>_______________________________________________
>>>Wg1-ar4-ch06 mailing list
>>>Wg1-ar4-ch06@xxxxxxxxx.xxx
>>>http://www.joss.ucar.edu/mailman/listinfo/wg1-ar4-ch06
>>
>>--
>>Professor Keith Briffa,
>>Climatic Research Unit
>>University of East Anglia
>>Norwich, NR4 7TJ, U.K.
>>
>>Phone: xxx xxxx xxxx
>>Fax: xxx xxxx xxxx
>>
>>http://www.cru.uea.ac.uk/cru/people/briffa/
>>_______________________________________________
>>Wg1-ar4-ch06 mailing list
>>Wg1-ar4-ch06@xxxxxxxxx.xxx
>>http://www.joss.ucar.edu/mailman/listinfo/wg1-ar4-ch06
>
>
>--
>______________________________________________________________
>Eystein Jansen
>Professor/Director
>Bjerknes Centre for Climate Research and
>Dep. of Earth Science, Univ. of Bergen
>All

Original Filename: 1105395606.txt | Return to the index page | Permalink | Later Emails

From: Jonathan Overpeck <jto@u.arizona.edu>
To: Valerie.Masson@xxxxxxxxx.xxx
Subject: Re: Glaciers Ch 6
Date: Mon, 10 Jan 2005 17:20:xxx xxxx xxxx
Cc: Keith Briffa <k.briffa@xxxxxxxxx.xxx>, Eystein Jansen <eystein.jansen@xxxxxxxxx.xxx>, trond.dokken@xxxxxxxxx.xxx, "Ricardo Villalba" <ricardo@xxxxxxxxx.xxx>

<x-flowed>
V - well said. Eystein and I will be working on your Holo section -
more tomorrow. thx, Peck

>2 comments
>
>- the various NH T reconstr use polar records : to my knowledge only
>use of melt index that itself does not calibrate properly in Mann's
>reconstruction. I sent you Keith winter d18O from Vinther 2003 which
>provides a reconstruction of NAO changes (I think this is the more
>detailed calibration study for Greenland isotopes).
>On a decadal time scale calibration studies for Antarctica (Vostok
>and Law Dome, inland vs coastal sites) using available instr records
>(50 years) show correct decadal scale temperature signals. Even at
>places with subannual resolution like Law Dome I think that you
>cannot use the isotopes on a yearly basis but only decadal scale.
>
>- tropical glaciers : works conducted here on Andean ice cores
>together with modelling of isotopes in a GCM all showed a consistent
>decadal variability on the 20th century, most of which interpreted
>to be related to precip change (see for instance Hoffmann et al,
>Science, "Taking the pulse of the tropical water cycle", Science,
>2003). For more ancient past periods it is thought that part of the
>signal is due to T (and vertical lapse rate change), part to
>precip.I would not like to cosign any text claiming for a T
>reconstruction based on Andean ice cores.
>
>
>Keith Briffa wrote:
>
>>I agree with suggestion - there is the problem of the isotopic
>>analyses from tropical (and to some extent polar) ice cores still .
>>I am not happy simply to show these in a Figure relating to the
>>large-scale temperature changes - because we are not sure of the
>>extent to which they can be interpreted as such . The various NH
>>reconstructions use some polar isotope records but looking at plots
>>of the tropical records throws up some strange behavior over the
>>last 2000 years . I am not happy to write about these as Valerie
>>and Olga are better qualified and because I would like to see more
>>formal calibration against even short temperature records . I have
>>therefore , not as yet explicitly said anything about these
>>tropical records. I will sendthe latest text and latest draft
>>FIgure 1 later today
>>
>>At 10:03 09/01/2005, Jansen@xxxxxxxxx.xxx wrote:
>>
>>>Dear Olga,
>>>My suggestion would be, and I believe this is echoed by Peck, is
>>>that the box
>>>we produce comes in the overall Holocene sub-chapter, thus to avoid
>>>repetition. The figure should mainly give syntheses of the glacier extent
>>>variations through the Holocene, if possible, or a fraction of it
>>>if data only
>>>exists e.g. for the last few millennia, for those regions where there is a
>>>reliable data set. Then with text explaining what we think drove these
>>>variations. I think it should be a box in Ch6, and could also include the
>>>recent trends I have just talked with Atle and he is able to contribute
>>>curves for Scandinavia and the Alps into a figure before the end of the week
>>>(in a couple of days). He feels putting something together for North America
>>>and perhaps New Zealand is feasible, but he cannot do this before the ZOD
>>>deadline. Perhaps you might be able? If we get something for the
>>>tropics from
>>>Lonnie and Ellen and what you have, I will be able to put this together in a
>>>figure for the box via assistance here. We can in such a figure leave space
>>>open for curves we anticipate including for the First Draft.
>>>It might be a good idea to in this figure also include the recent,
>>>instrumental evidence for the same regions, akin to what will be in Ch4, and
>>>of course, in the next iteration come back to possible joint Ch4
>>>and 6 figure.
>>>
>>>How does this sound?
>>>
>>>Cheers,
>>>Eystein
>>
>>
>>--
>>Professor Keith Briffa,
>>Climatic Research Unit
>>University of East Anglia
>>Norwich, NR4 7TJ, U.K.
>>
>>Phone: xxx xxxx xxxx
>>Fax: xxx xxxx xxxx
>>
>>http://www.cru.uea.ac.uk/cru/people/briffa/
>
>
>
>
>Attachment converted: Macintosh HD:masson 5.vcf (TEXT/ttxt) (000C2383)

--
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: xxx xxxx xxxx
fax: xxx xxxx xxxx
http://www.geo.arizona.edu/
http://www.ispe.arizona.edu/
</x-flowed>

Original Filename: 1105462633.txt | Return to the index page | Permalink | Later Emails

From: Eystein Jansen <eystein.jansen@xxxxxxxxx.xxx>
To: Valerie.Masson@xxxxxxxxx.xxx, masson@xxxxxxxxx.xxx
Subject: Re: Urgent - pls respond FAST
Date: Tue, 11 Jan 2005 11:57:13 +0100
Cc: Jonathan Overpeck <jto@u.arizona.edu>, Jean-Claude Duplessy <Jean-Claude.Duplessy@xxxxxxxxx.xxx>, raynaud@xxxxxxxxx.xxx, cddhr@xxxxxxxxx.xxx, rahmstorf@xxxxxxxxx.xxx, dolago@xxxxxxxxx.xxx, Keith Briffa <k.briffa@xxxxxxxxx.xxx>, Fortunat Joos <joos@xxxxxxxxx.xxx>

<x-flowed>
Valerie,
Thanks for putting together the chaper so well. I
think it is quite comprehensive now. I have made
a few changes in the enclosed document and also
added a comment( pops up if you mark the yellow
field).
I tend to like the questions, and think it
highlights the relevance elements of the chapter.
The missing references I have suggested, we can
take care of in the final editorial process from
our side.
As for figures one figure showing the evidence
for Holocene warrmt and the abrupt character of
the 5-4ka cooling, perhaps with a low latitude
data set that shows another evolution would be
good to have, as you indicate, but we cannot
bombard the chapter with wiggly lines, so the
most characteristic exampes would be best.
If you need high lat.ocean data I can provide, or
perhaps NorthGrip O-18 is best?
Cheers,
Eystein

Cheers,
Eystein

At 11:13 +0xxx xxxx xxxx, Valerie Masson-Delmotte wrote:
>Valerie Masson-Delmotte wrote:
>
>>I tried the question style for the Holocene
>>section... Any feedback would be appreciated
>>together with missing references (Fortunat).
>>Valerie.
>>
>>Jonathan Overpeck wrote:
>>
>>>Hi all leads and seconds of our Chap 6.5
>>>Synthesis sections. Fortunat came up with a
>>>interesting way to highlight what's important
>>>and why in his section 6.5.3, and Eystein and
>>>I would like feedback from you - particularly
>>>the leads - on whether this approach would
>>>work for each of your subsections.
>>>
>>>He used a question and answer style. If people
>>>do not like this then the question at the
>>>beginning of the paragraphs can of course be
>>>easily dropped and replaced by a statement.
>>>BUT, what do you say about using this
>>>convention throughout 6.5??? Note that some
>>>sections might have much more text per unit
>>>question.
>>>
>>>Please respond asap. Thanks, Peck and Eystein
>>
>>
>>
>
>
>
>Attachment converted: Sauvignon blanc:Holocene-VMD3.doc (WDBN/MSWD) (004575F7)
>Attachment converted: Sauvignon blanc:masson 8.vcf (TEXT/ttxt) (004575F8)

--
______________________________________________________________
Eystein Jansen
Professor/Director
Bjerknes Centre for Climate Research and
Dep. of Earth Science, Univ. of Bergen
All

Original Filename: 1105543270.txt | Return to the index page | Permalink | Later Emails

From: Jonathan Overpeck <jto@u.arizona.edu>
To: derzhang@xxxxxxxxx.xxx
Subject: Re: Re: [Wg1-ar4-ch06] URGENT - Deadline approaching
Date: Wed, 12 Jan 2005 10:21:xxx xxxx xxxx
Cc: Eystein Jansen <eystein.jansen@xxxxxxxxx.xxx>, r.ramesh@xxxxxxxxx.xxx, dolago@xxxxxxxxx.xxx, Jean-Claude Duplessy <Jean-Claude.Duplessy@xxxxxxxxx.xxx>, Keith Briffa <k.briffa@xxxxxxxxx.xxx>

Hi Prof. Zhang: thanks for your email and good to hear about your book. I will send the
reference file to the LAs for them to incorporate as appropriate. You will also be editing
the ZOD when it's complete, or of specific sections before then if you ask the appropriate
leader of a section of interest (see previous listserv email with this list in case you
don't remember from Italy).

Regarding 6.5.9, I will cc this to Dan and Ramesh so you can coordinate with them
directly. This is the process we have adopted for all subsections so we don't waste time
with the CLA's having to relay messages. Go direct...

I will also CC to Jean-Claude and Keith, so they make sure they have checked your input.

Many thanks, Peck

Original Filename: 1105556495.txt | Return to the index page | Permalink | Later Emails

From: Keith Briffa <k.briffa@xxxxxxxxx.xxx>
To: Eystein Jansen <eystein.jansen@xxxxxxxxx.xxx>
Subject: Re: where I am !!!! !
Date: Wed Jan 12 14:01:xxx xxxx xxxx

Eystein
in theory - it is supposed to be finished. I would just remove the two sections I suggested
(or certainly move the regional simulation stuff into Ricardo's section. How does end note
cope with references that are not published?
Keith
At 13:26 12/01/2005, you wrote:

Hi Keith,
I am in transit back to Bergen where there is a strong storm at present, but just a
query to ask what you think a a realistic time fframe for your part. I will be reding
through it on the way. If you have problems getting the references in, this is
something we can help with, if you just write i text author name, year and paper, then
we download from the ISI base and enter into End Note here, just to help you
prioritising the text and figures.
Thanks for all your efforts. This is a critical part of the Chapter and the most complex
and it seems to progress well, despite the strains.
Cheers,
Eystein

Basically , I need to send this to you to because there comes a point when I am just not
able to read it objectively.
I would really like you both - and David and Stefan (I am ccing to them only) to look
at it . Obviously it has grown too much, but the information in here is in my opinion
all important.
I suggest removing the regional simulations stuff from the end (as David said earlier!)
but feel this should be somewhere - also (sorry Eystein) perhaps the ocean section
should go? I have dropped the proposed Figure 2 _ after wasting a lot of time on it -
there are too many problems with getting and understanding data - and then making any
sensible conclusion on the basis of it. We really must have the two Figures left though
- or some variants (these need borehole curves including and some way of indicating
envelope of uncertainty around all reconstructions - perhaps as gray shading of
different darkness depending on how may confidence limits overlap).
I would really appreciate a dispassionate look by all of you at the conclusions drawn
after the the desciption of both Figures - in the light of the discussion we had about
interpreting these Figures. I am really happy if you and David and Stefan (and
Fortunat?) consider what is worth and not worth trying to say re the implications of
these Figures, beyond the TAR. I can not tell if what I am saying is balanced (I know
Esper reconstruction is very hairy and ECHO-G run has much too great long-term
variability - but no evidence PUBLISHED to support this - yet at least). Is what I say
about the implications of the reconstructions banal?
I have been battling with teaching today and fucked up course scheduling by the
administration that has outraged some students. Tomorrow I must take daughter back for
new term in Cambridge - and now must work on proposal for Russian who leaves Thursday
and needs to submit before then.
Do have a look and trim , cross reference as needed. The nightmare with these references
continues also and I will have to get someone to help out here - incidentally our
secretary has gone absent for a month . I will be back in hopefully by tomorrow
afternoon . The conclusions (bullets?) should be very brief - but can not see them yet -
suggestions welcome
I can try to do something for the methods but would rather you just told me exactly what
is needed. I will then work on this Thursday and likely happy to accept what you say re
this text. I know I have not contributed to the discussing on other sections - very
frustrating - but must wait til after ZOD . Sorry
Keith
--
Professor Keith Briffa,
Climatic Research Unit
University of East Anglia
Norwich, NR4 7TJ, U.K.
Phone: xxx xxxx xxxx
Fax: xxx xxxx xxxx
[1]http://www.cru.uea.ac.uk/cru/people/briffa/
Attachment converted: Sauvignon blanc:IPCCFARxxx xxxx xxxx.doc (WDBN/MSWD) (00459793)

--
______________________________________________________________
Eystein Jansen
Professor/Director
Bjerknes Centre for Climate Research and
Dep. of Earth Science, Univ. of Bergen
All

Original Filename: 1105566936.txt | Return to the index page | Permalink | Later Emails

From: Jonathan Overpeck <jto@u.arizona.edu>
To: Bette Otto-Bleisner <ottobli@xxxxxxxxx.xxx>, Keith Briffa <k.briffa@xxxxxxxxx.xxx>, Tim Osborn <t.osborn@xxxxxxxxx.xxx>, Eystein Jansen <eystein.jansen@xxxxxxxxx.xxx>, peltier@xxxxxxxxx.xxx, rahmstorf@xxxxxxxxx.xxx, cddhr@xxxxxxxxx.xxx
Subject: Urgent - FINAL review/edits of 6.5.8 Sensitivity
Date: Wed, 12 Jan 2005 16:55:xxx xxxx xxxx
Cc: raynaud@xxxxxxxxx.xxx, Jean-Claude Duplessy <Jean-Claude.Duplessy@xxxxxxxxx.xxx>

Hi all on the list above... Some of you have received this already straight from David, but
some other key people have not. Eystein and I would appreciate it very much if you would
please read/comment/and edit the attached section 6.5.8 (Sensitivity) NO LATER THAN
THURSDAY NOON, Eastern time (6PM GMT).

Please send responses to all on the address list ABOVE, plus Peck.

Thanks, Peck

X-Sieve: CMU Sieve 2.2
X-Sender: drind@xxxxxxxxx.xxx
Date: Wed, 12 Jan 2005 13:29:xxx xxxx xxxx
To: joos <joos@xxxxxxxxx.xxx>
From: David Rind <drind@xxxxxxxxx.xxx>
Subject: Re: Fwd: Re: Fwd: 6.5.8 Sensitivity
Cc: David Rind <drind@xxxxxxxxx.xxx>,
Jonathan Overpeck <jto@u.arizona.edu>,
Dominique Raynaud <raynaud@xxxxxxxxx.xxx>,
Eystein Jansen <eystein.jansen@xxxxxxxxx.xxx>,
trond.dokken@xxxxxxxxx.xxx, peltier@xxxxxxxxx.xxx,
Jean-Claude Duplessy <Jean-Claude.Duplessy@xxxxxxxxx.xxx>,
rahmstorf@xxxxxxxxx.xxx, cddhr@xxxxxxxxx.xxx
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Dear Fortunat (and others),

Here is the revised section 6.5.8. I've put in most of your changes (and also most of
those suggested by Stefan, particularly with regards to clarifying the sign of the
radiative forcing). Most importantly, I've removed the table - I agree it seems to imply
a solidity that is really not there. The one thing I have not done is condense it
greatly (of course!). The real reason for going into such detail, rather than just
saying, "well, the forcing and response are uncertain, so we can't conclude anything",
is I think it's important to show that paleoclimate scientists have gone to some effort
to try to deduce climate sensitivity from the paleorecord, the parameter that is
probably of most interest to IPCC. In that respect the details are important, as are the
magnitudes of uncertainty represented in the different studies. Obviously, at any point
in the proceedings the section can be shortened, but I thought it useful to start with
this level of quantification, and show paleoclimate has this similarity with the rest of
IPCC in addition to more qualitative concepts.

I've responded to your individual comments below.

At 6:15 PM +0100 1/11/05, joos wrote:

Dear David,
Here my comments on the updated climate sensitivity section. Please
apologize if I formualate my comments straight away, but I need to leave
very soon. Many of my comments might have to do with presentation.
Your main conclusions in paragraph f are fine.
My view is that it would be ideal to address the issue from a
probabilistic view point. this is of course not always possible.
1) Maunder Minimum section:
Several studies using Monte Carlo approaches show that almost any
climate sensitivity is posssible when taking into account uncertainties
in radiative forcing input data as well as observational records over
the 20 century as constraints. See the Paris report for more
information.
The uncertainty does not only arise from indirect aerosol effect, but
also form the whole range of forcing agents that all have an uncertainty
attached. E.g. Reto Knutti did some evaluation of his results where he
assumed that the aerosol forcing is exactly know (No error) -> even then
climate sensititivity remains unconstraint. Clearly, uncertainty is
growing when going further back in time than the last century as done
here. Then, the numbers provided in the table are useless, as you now
state in the last sentence of the revised text.
2) Other sections:
I think similar concerns also hold for the other sections. For example,
the LGM global cooling is very uncertain. I have just heard yesterday a

talk by Ralph Schneider who showed how different SST reconstructions
(Alkenone, Cd/Ca, MAT, radiolare etc) disagree. global SST cooling might
be anywhere between 0 and 4 K or so. Of course, CLIMAP and the recent
GLAMAP update provide a reasonable estimate. However, the point is that
uncertainies are huge.
The table is a very focused and stand alone thing for the reader. It
gives the impression that climate sensitivity for different period can
be well evaluated. However, this is not the case.
3) My conclusion:
- The table should be dropped. I have quite a strong feeling here, as it
seems to me that the number in the table are very hard to defend and
should not be made prominent.

The table and reference to it has been dropped.

- The whole section should be condensed considerably. Your main
conclusions in paragraph f are fine.

Well, removing the table will shorten this section!

Further comments:
1) section d) 1. para: solar forcing reduction estimate range up to

0.65% for MM e.g. Reid, 97 and Bard et al.

Correction made, and reference added (and I also corrected the numbers as Stefan
suggested, although the upper number is actually larger given the Reid estimate).

2) section d, last para equilibrium
The statement that transient effects are not important is very hard to
defend:
2a) The warming and forcing up to today is considered. Certainly, we are
now far from equilibrium ( a lag of 30 years or so).
2b) the volcanic forcing is very pulse like and I do not see how the
equilibrium concept holds here. It can only be evaluated in a transient
way.
3c) The MM is probably not in equilibrium climate, as solar forcing has
likely varied over the MM as indicated by radiocarbon, althoug sunspots
were not present

I've removed the word "transient" but I have justified the equilibrium aspect of the
sentence with a reference (we investigated that issue by running from 1500 through the
Maunder Minimum, and seeing what the prior changes in solar forcing did to the Maunder
Minimum cooling - the effect, as noted in the reference, was small in our model).

3) section b) end of 1. para: How should such a 'general climate
sensitivity' be defined?

For now I've simply suggested what should also be factored in; I don't know that it's
our place to come up with a new definition per se, although if IPCC is interested, we
could try!

4), section c) Somewhat a mix of model and observations. end of 2 para:
It is not clear which forcing was operating in these different models
(at least it is not stated in the text) and hence one can not directly
imply a climate sensitivity in the way done here. For this the forcing
that went into the model simulations must be known.

I looked at each of the references and saw what forcing they actually used - they were
all very similar except for one which used current orbital parameters (not really
important). This comment is now included.

Hope this is useful and looking foreward to further debate the issue.

Thanks for the comments!

David

ps - Jonathan, the attached Endnote library includes the references we discussed
yesterday, as well as all the ones relevant for this section.

--

///////////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////

--

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: xxx xxxx xxxx
fax: xxx xxxx xxxx
http://www.geo.arizona.edu/
http://www.ispe.arizona.edu/

Attachment Converted: "c:eudoraattachnewest_6.5_2.8.doc" Attachment Converted:
"c:eudoraattachIPPC_2007_1_Rind_Copy"

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From: Jonathan Overpeck <jto@u.arizona.edu>
To: Keith Briffa <k.briffa@xxxxxxxxx.xxx>, t.osborn@xxxxxxxxx.xxx
Subject: methods - section 6.2.2
Date: Wed, 12 Jan 2005 22:57:xxx xxxx xxxx
Cc: Eystein Jansen <eystein.jansen@xxxxxxxxx.xxx>, joos <joos@xxxxxxxxx.xxx>, Valerie Masson-Delmotte <Valerie.Masson@xxxxxxxxx.xxx>

<x-flowed>
Hi all: Keith and Tim asked for specific requests in terms of what
you could do for section 6.2.2. I'm hoping Valerie and Fortunat have
already made enough progress that they can ask, but here's my take:

1. you have lots of methodology material in your 6.3.2.1, and this is
good. It would be good to refer to this from the earlier, more
general 6.2.2

2. the goal of 6.2.2 is to give the reader more confidence in paleo
and to get them to read on with confidence that what they read will
be of use

3. I suspect that the format V and F will be working around will be
one that can first highlight chronological issues (that we can date
some proxies very well, and that's what we focus on in this chapter
primarily). It would be good to have the usual comforting comments
about tree rings and other annual proxies.

4. The, it would be good to have the basics on how proxies reflect
climate, and how we know we understand the relationship. That it is
useful even if the proxy is responding to things other than climate.
Seasonality, etc. Include brief overview of calibration,
verification. you know the drill.

5. keep it short and not too detailed. Use lots of references -
including to the most recent stuff.

6. I'm sure we'll end up modifying/improving later after we figure
out what to do with the appendix

7. Need to work fast, very fast, but hopefully V and F have made real
progress already.

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: xxx xxxx xxxx
fax: xxx xxxx xxxx
http://www.geo.arizona.edu/
http://www.ispe.arizona.edu/
</x-flowed>

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From: Jonathan Overpeck <jto@u.arizona.edu>
To: Keith Briffa <k.briffa@xxxxxxxxx.xxx>, t.osborn@xxxxxxxxx.xxx
Subject: Comments on 6.3.2.1
Date: Wed, 12 Jan 2005 22:58:xxx xxxx xxxx
Cc: rahmstorf@xxxxxxxxx.xxx, drind@xxxxxxxxx.xxx, Eystein Jansen <eystein.jansen@xxxxxxxxx.xxx>, joos <joos@xxxxxxxxx.xxx>

<x-flowed>
Keith, Tim (and friends- please read below and provide your comments
THURS too) - just finished reading your draft and my primary reaction
is one of great relief and admiration. You've done an excellent job.
I'm sure things will look different in the end, but for the ZOD, this
lays things out just fine.

That said, here are comments. More are in the attached draft w/ track changes

1. still need to see the figs - ok to state what still has to be done
(as you have)
2. regarding the ocean section, I think some of it should stay in -
both as a placeholder for other relevant stuff, and because it is
important. See attached. It would be good if EYSTEIN would look at my
comments for this section and provide the needed minor help - we need
the punchline/bullet - how does the 20th century compare with the
previous part of the record (you say it shows the warming, but then
don't go the next step.
3. THIS IS THE ONLY COMMENT THAT WILL TAKE MORE THAN A FEW MINUTES -
can we get THE word on the MWP in before hydro? Heck, I'd even
support a small (smaller than the other ones) box. There is lots of
debate about the MWP,. and we need to weigh in. Was it global,
hemispheric, regional only (e.g., Europe and N. Atlantic - can then
refer back to it in ocean section)? Was it one synchronous warm event
or a bunch of shorter regionally asynchronous events? Warmer than
20th? Late 20th? (think you answered this, but need to nail it!).
Cite the cast of papers you've already discussed, plus Bradley et al
Science 03.
4. what you say is balanced, and it's ok to note in the text where
you anticipate serious improvement w/ more published paper support -
e.g., Esper (you're doing a paper on this, no?) and ECHO-G.
5. have to have boreholes on Figs too - that would be more important
now than uncertainty estimates around all recons - the latter is
harder, but in any case, say what you intend to add after ZOD.
6. see text - minor edits
7. I can make draft bullets from what you sent

Guys - it was worth the wait. Hope you can take advantage of the
relatively minor edits required and help some with other sections as
asked for.
--
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: xxx xxxx xxxx
fax: xxx xxxx xxxx
http://www.geo.arizona.edu/
http://www.ispe.arizona.edu/
</x-flowed>

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From: Jonathan Overpeck <jto@u.arizona.edu>
To: Keith Briffa <k.briffa@xxxxxxxxx.xxx>
Subject: Re: Peck your comments...
Date: Thu, 13 Jan 2005 09:53:xxx xxxx xxxx
Cc: Eystein Jansen <eystein.jansen@xxxxxxxxx.xxx>

<x-flowed>
Hi Keith -

1) ok on the refs - send tomorrow
2) glad you're keen for the box - it can't be too long - maybe shot
for ca. 400 words? After the ZOD is done, I'm sure we can tune to the
correct balance of info. A fig is ok if it's compelling. The box will
either be 6.1 or 6.2 depending on whether you refer to it in your
section before or after the glacier box. I'm guessing it'll be 6.1
and come first, but it's your call. Think of a title for the box -
something like "Box 6.1: The Medieval Warm Period" or maybe something
more catchy. Can't be too glib.
3) glad you have some borehole in there. Of course, you'll be at the
front of the line for dealing with the grief we get no matter what
choice we make. So the key is to go with what can be best justified.
Your section has this nice balance already.

Thanks for getting Tim (and you as time permits) to work on those
other sections - VERY important too. But, your section is the most
important.

thx, Peck

>...are really welcome. Am now incorporating them , plus doing some
>editorial bits - though will wait on Eystein to send replacement
>ocean bit . Having to get one of my people to do the references but
>not likely these will arrive til tomorrow. The main point to discuss
>is your comment on the MWP . I like the idea of a box. This IS
>sufficiently important to warrant it - in the context that most
>people say "it was warm/warmer than now then so disproves anthro
>effect - we should address this explicitly. I will have a go - but
>need to know how many words and Figure(s) allowed. We can simply
>just refer to this box in a couple of places in existing text. Sorry
>about Figures - now got some (2 ) borehole lines in (but may need
>more - reluctant to use Huang and Pollack original though because
>obviously much too cold on basis of simple regional averaging
>biases. Will send latest version (without box on MWP) tonight my
>time.
>Keith
>
>--
>Professor Keith Briffa,
>Climatic Research Unit
>University of East Anglia
>Norwich, NR4 7TJ, U.K.
>
>Phone: xxx xxxx xxxx
>Fax: xxx xxxx xxxx
>
>http://www.cru.uea.ac.uk/cru/people/briffa/

--
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: xxx xxxx xxxx
fax: xxx xxxx xxxx
http://www.geo.arizona.edu/
http://www.ispe.arizona.edu/
</x-flowed>

Original Filename: 1105653626.txt | Return to the index page | Permalink | Later Emails

From: David Rind <drind@xxxxxxxxx.xxx>
To: Stefan Rahmstorf <rahmstorf@xxxxxxxxx.xxx>
Subject: Re: 6.5.8 revisions
Date: Thu, 13 Jan 2005 17:00:xxx xxxx xxxx
Cc: David Rind <drind@xxxxxxxxx.xxx>, Tim Osborn <t.osborn@xxxxxxxxx.xxx>, Jonathan Overpeck <jto@u.arizona.edu>, Keith Briffa <k.briffa@xxxxxxxxx.xxx>, Eystein Jansen <eystein.jansen@xxxxxxxxx.xxx>, FortunatJoos@xxxxxxxxx.xxx

Here are my responses to Stefan's comments. While I could have made each of these points in
the document itself, it is already sufficiently long that Jonathan had me cut it before
most of you guys saw it.

At 8:53 PM +0100 1/13/05, Stefan Rahmstorf wrote:

Hi folks,
on the topic of climate sensitivity. I just lost a long mail on it due to a software
crash, so sorry if I'm brief now.

I think it makes no sense for the purpose of the IPCC to discuss a climate sensitivity
to orbital forcing - if such a thing can be defined at all. The first-order idea of
orbital forcing is that in annual global mean it is almost zero - and in any case the
large effect orbital forcing has on climate has very little to do with its global mean
value. Hence, we'll confuse people by discussing it in this way, and even citing numbers
for it. For the purpose of IPCC, I think climate sensitvity should refer to climate
sensitivity wrt. greenhouse gases.

The point here is that climate can be forced by other factors than simply a global, annual
average radiation change, which is the metric now being used. The orbital forcing induced
changes are wonderful examples of this, hence the paleoclimate chapter is a perfect place
to discuss it. Variations in seasonal and latitudinal forcing clearly have had a major
impact on climate, including forcing of ice ages, yet the annual average radiative change
is small. The importance of this with respect to IPCC is that other climate forcings can
also affect the seasonal and latitudinal distribution of radiation - aerosols, land surface
changes, and even solar radiation (considering cloud cover distributions) - hence they too
may have a disproportionate influence compared to their annual global average magnitude.
What is said in this subsection is simply that this one metric clearly fails with respect
to the major variations in paleoclimate, and as a general rule, there should be room for an
expanded concept (which may then have utility for current and future climate forcing as
well).

Also, it is questionable to discuss climate sensitivity for uncoupled models, especially
for glacial times - Ganopolski et al. (Nature 1998) have shown that glacial climate
looks very different with mixed layer ocean vs. coupled. I think for a 2007 IPCC report
we shouldn't be discussing old uncoupled runs when coupled model results are available.
(And it is a little odd that the above paper, the first coupled model simulation of
glacial climate, cited over 150 times so far, is ignored here in the discussion of the
last glacial maximum - if you do a search on the Google Scholar engine for the key words
"Last Glacial Maximum", you'll find it's the second-most cited paper on this topic after
the Petit et al. Vostok data paper.)

In fact, most if not all of climate sensitivity measurements have been done for what Stefan
calls "uncoupled models", atmospheric models coupled to mixed layer ocean models. The
results from all prior IPCC reports give sensitivities from precisely these types of models
- for the basic reason that almost no one has ever run a coupled model for 2CO2 to
equilibrium. The other disadvantage of coupled models in this regard is that their control
run, if simulated long enough, often does not reproduce the current climate in important
respects - one is then getting a climate sensitivity with respect to something far removed
from the current climate, so what good is it? The fact that models coupled to a dynamic
ocean and those coupled to mixed layer oceans may get different responses - and one can see
from the numbers that the responses are actually fairly similar in general - can be related
to the ocean dynamics changes; as the text notes, that is considered a feedback in this
subsection, and therefore an appropriate part of the climate sensitivity calculation.

I still think it makes no sense to say that climate sensitivity depends on the sign of
the forcing. Talking about greenhouse gases: whether you will do an experiment going
from 280 ppm to 300 ppm, or the other way round from 300 ppm to 280 ppm, should give you
the same climate sensitivity. Perhaps you mean that going from 280 to 300 will give a
different result compared to going from 280 to 260, but then you're really comparing
different mean climates. I think this "directionality" of climate sensitivity is not a
good concept.

It's not the forcing per se that's the issue here, it's the feedbacks that potentially can
alter the climate sensitivity to the sign of the forcing.

It has been suggested in the past that climate sensitivity is larger to cooling
perturbations then to warming ones, and we ourselves have found that result in some earlier
model runs. The standard reason given is that with a cooling climate perturbation, sea ice
can expand further equatorward, to cover a broader area, and intersect more solar radiation
- therefore providing a more positive feedback to the cooling. In a warming climate, the
sea ice retreats and intersects less radiation - but the sunlight-weighted area is smaller
in the regions it is retreating to, so its positive feedback to the warming is not as
large.

However - water vapor works the opposite way. Given the exponential dependence of water
vapor on temperature, in a warming climate the added temperature would allow for a greater
water vapor change (increase) than would occur with a cooling climate of the same
magnitude. Hence the water vapor feedback should be greater in a warming climate.

So the answer is - nobody knows. Jim Hansen did a survey of people at GISS recently to see
what the general opinion was for a paper he's working on (and sending around). Since
paleoclimates have suffered both positive and negative forcings (in the examples given in
this section), and since we don't know the answer to this question, we can't really say
whether the sign of the forcing is important or not. So I've left it as an open question,
with the possibility that it might matter.

Relating forcing to response, the sensitivity from the models is then on the order of
0.6

What are others looking for?