Hi Mike,
I agree completely with your analysis.  I don't get so many requests as you, but even so
get enough to mean that I ignore most - I just pick a few at random to respond to.  As Phil
is away, I picked this.  He's already come back with a second request, which I answered,
but that's all he'll get from me. I'll
At 13:56 03/10/2003, you wrote:
Tim,
Many kind thanks for going out of your way to respond to this. Colleagues have
increasingly been warning me against "taking the bait" too often (which this seems
another attempt at), and so I resisted giving the detailed response that you have nicely
provided (as well as I could have myself, I might add). They dried to bog Ben Santer
down with distractions, they've been trying to do the same to me, and its supposed to be
a warning to the rest of us. So the trick is to find the middle ground between
responding to most egregious and potentially damaging accusations, and not swinging at
every ball they throw your way. Its thus very helpful if friends and colleagues can take
up a bit of the slack now and then, as you have so graciously done...
This guy has written such trash before on the subject, that I assume he's out to do a
hatchet job and there is little that we can do to change that. But your response was
very helpful. It will be interesting to see what comes of this,
thanks once again,
mike
p.s. I never saw the graph in Fred Pearce's piece, since the online version didn't show
it. But it does sound problematic from what you describe.
At 9:56 AM 10/3/2003 +0100, Tim Osborn wrote:
Dear Mr. Matthews,
I have not read the criticism on the website you refer to, but will add to Mike Mann's
response in a small, but hopefully helpful, way.
Comparison of the Mann and Jones proxy-based reconstruction with instrumental
temperature data *is* a valid comparison to make, provided that the reconstruction is
*calibrated* to represent the instrumental record and provided that the *uncertainties*
in the calibration are taken into account when making the comparison.
That is, after all, the purpose of calibration - to allow two different data sets to be
compared!
As is clear from their article, Mann and Jones do undertake a careful calibration and
only make comparisons after the calibration, and their comparison figure includes their
estimated uncertainty range.  Thus the conclusions they draw (regarding whether recent
warming is unprecedented) are valid and are supported by their analysis.
This does not mean that future work, perhaps using new proxy records or different
methods for calibration or for estimating calibration uncertainties, will not change
those conclusions.  But it remains true that their conclusions are supported by their
analysis.
As an example of a poor comparison, see the piece by Fred Pearce on page 5 of 12 July
2003 issue of New Scientist.  This is a short news article about the Mann and Jones
paper, and it unfortunately shows a comparison figure without the associated calibration
uncertainties.  That is not a good comparison.  I mention this in case you were thinking
of including a diagram in your article, perhaps showing the Mann and Jones results.  If
you do, then it will only be valid for comparing the recent instrumental temperatures
with the proxy-based reconstruction of earlier temperatures if the reconstruction
uncertainties are included.  Try to avoid the mistake that Fred Pearce made.
Regards
Tim
At 21:11 02/10/2003, Michael E. Mann wrote:
Dear Mr. Matthews,
Unfortunately Phil Jones is travelling and will probably be unable to offer a separate
reply. Since your comments involve work that is his as well, I have therefore taken the
liberty of copying your inquiry and this reply to several of his British colleagues.
The comparisons made in our  paper are well explained therein, and your statements belie
the clearly-stated qualifications in our conclusions with regard to separate analyses of
the Northern Hemisphere, Southern Hemisphere, and globe.
An objective reading of our manuscript would readily reveal that the comments you refer
to are scurrilous. These comments have not been made by scientists in the peer-reviewed
literature, but rather, on a website that, according to published accounts, is run by
individuals  sponsored by ExxonMobile corportation, hardly an objective source of
information.
Owing to pressures on my time, I will not be able to respond to any further inquiries
from you. Given your extremely poor past record of reporting on climate change issues,
however, I will leave you with some final words. Professional journalists I am used to
dealing with do not rely upon un-peer-reviewed claims off internet sites for their
sources of information. They rely instead on peer-reviewed scientific research, and
mainstream, rather than fringe, scientific opinion.
Sincerely,
Michael E. Mann
At 08:30 PM 10/2/2003 +0100, Robert Matthews wrote:
Dear Professor Mann
I'm putting together a piece on global warming, and I'll be making reference to your
paper in Geophysical Research Letters
with Prof Jones on "Global surface temperatures over the past two millennia".
When the paper came out, some critics argued that the paper actually showed that there
have been three periods in the last 2000 years which were warmer than today (one just
prior to AD 700, one just after, and one just prior to AD 1000).  They also claimed that
the paper could only conclude that current temperatures were warmer if one compared the
proxy data with other data sets. (For an example of these arguments, see:

03/v6n34c4.htm)
I'd be very interested to include your rebuttals to these arguments in the piece I'm
doing. I must admit to being confused by why proxy data should be compared to
instrumental data for the last part of the data-set. Shouldn't the comparison be a
consistent one throughout ?
With many thanks for your patience with this
Robert Matthews
Dr Timothy J Osborn
Climatic Research Unit
School of Environmental Sciences, University of East Anglia
Norwich  NR4 7TJ, UK
e-mail:   t.osborn@uea.ac.uk
phone:    +44 1603 592089
fax:      +44 1603 507784
web:      [1]~timo/
sunclock: [2]~timo/sunclock.htm
______________________________________________________________
Professor Michael E. Mann
Department of Environmental Sciences, Clark Hall
University of Virginia
Charlottesville, VA 22903
_______________________________________________________________________
e-mail: mann@virginia.edu   Phone: (434) 924-7770   FAX: (434) 982-2137
[3]
References
1. ~timo/
2. ~timo/sunclock.htm
3.


Thanks Tom,
In fact, I'm almost done with a brief (
, rbradley@geo.umass.edu
, Keith Briffa
, Tom Crowley, "Malcolm Hughes"
, omichael@princeton.edu
, Tim Osborn
, Jonathan Overpeck
, Scott Rutherford
, Kevin Trenberth
, Tom Wigley
From: "Michael E. Mann"
Subject: Fwd: EOS: Soon et al reply
Comments?
Mike
Delivered-To: mem6u@virginia.edu
Date: Sat, 04 Oct 2003 12:33:04 -0400
From: Ellen Mosley-Thompson
Subject: EOS: Soon et al reply
X-Sender: ethompso@pop.service.ohio-state.edu
To: "Michael E. Mann"
Cc: lzirkel@agu.edu
, jjacobs@agu.org
X-Mailer: QUALCOMM Windows Eudora Version 6.0.0.22
Dear Dr. Mann (and co-authors of the Forum piece that appeared in EOS),
Dr. Willie Soon and his co-authors have submitted a reply to your Forum piece that I
have accepted.   Let me outline below the official AGU procedure for replies so that you
know the options available.  I have sent these same instructions to Dr. Soon.
As you wrote the original piece you now have the opportunity to see their comment
(attached) on your Forum piece.  You may decide whether or not to send a reply.  If you
choose not to reply - their reply will be published alone.
Should you decide to reply then your response will be published along with their comment
on your paper.   One little twist is that if you submit a reply, they are allowed to see
the reply, but they can't comment on it.   They have two options: they can let both
their and your comments go forward and be published together or (after viewing your
reply) they also have the option of withdrawing their comment. In the latter case, then
neither their comment or your reply to the comment will be published.  Yes this is a
little contorted, but these are the instructions that I received from Judy Jacobs at
AGU.
I have attached the pdf of their comment.  Please let me know within the next week
whether you and your colleagues plan to prepare a reply.  If so, then you would have
several weeks to do this.
I have copied Lee Zirkel and Judy Jacobs of AGU as this paper is out of the ordinary and
I want to be sure that I am handling all this correctly.
I look forward to hearing from you regarding your decision on a reply.
Best regards,
Ellen Mosley-Thompson
EOS, Editor
cc: Judy Jacobs and Lee Zirkel
attachment
______________________________________________________________
Professor Michael E. Mann
Department of Environmental Sciences, Clark Hall
University of Virginia
Charlottesville, VA 22903
_______________________________________________________________________
e-mail: mann@virginia.edu
Phone: (434) 924-7770   FAX:
(434) 982-2137
[19]
______________________________________________________________
Professor Michael E. Mann
Department of Environmental Sciences, Clark Hall
University of Virginia
Charlottesville, VA 22903
_______________________________________________________________________
e-mail: mann@virginia.edu
Phone: (434) 924-7770   FAX:
(434) 982-2137
[21]
-- ****************
Kevin E. Trenberth                              e-mail: trenbert@ucar.edu
Climate Analysis Section, NCAR                  [23]www.cgd.ucar.edu/cas/
P. O. Box 3000,                                 (303) 497 1318
Boulder, CO 80307                               (303) 497 1333 (fax)
Street address: 1850 Table Mesa Drive, Boulder, CO  80303
______________________________________________________________
Professor Michael E. Mann
Department of Environmental Sciences, Clark Hall
University of Virginia
Charlottesville, VA 22903
_______________________________________________________________________
e-mail: mann@virginia.edu   Phone: (434) 924-7770   FAX: (434) 982-2137
[25]
______________________________________________________________
Professor Michael E. Mann
Department of Environmental Sciences, Clark Hall
University of Virginia
Charlottesville, VA 22903
_______________________________________________________________________
e-mail: mann@virginia.edu   Phone: (434) 924-7770   FAX: (434) 982-2137
[26]
References
1. mailto:ammann@ucar.edu
2. mailto:rbradley@geo.umass.edu
3. mailto:k.briffa@uea.ac.uk
4. mailto:mhughes@ltrr.arizona.edu
5. mailto:omichael@princeton.edu
6. mailto:t.osborn@uea.ac.uk
7. mailto:jto@u.arizona.edu
8. mailto:srutherford@rwu.edu
9. mailto:trenbert@cgd.ucar.edu
10. mailto:wigley@ucar.edu
11. mailto:mann@virginia.edu
12. mailto:mem6u@virginia.edu
13. mailto:thompson.4@osu.edu
14. mailto:ethompso@pop.service.ohio-state.edu
15. mailto:mann@virginia.edu
16. mailto:lzirkel@agu.edu
17. mailto:jjacobs@agu.org
18. mailto:mann@virginia.edu
19.
20. mailto:mann@virginia.edu
21.
22. mailto:trenbert@ucar.edu
23.
24.
25.
26.


HI Tom,
My understanding of the papers from the borehole community ever since the 1997 GRL article
by Huang et al is that they no longer believe that the data has proper sensitivity to
variations prior to about AD 1500--in fact, I don't believe anyone in that community now
feels they can meaningfully go farther back that that. Huang contributed the section on
boreholes in chapter 2 for IPCC (2001), and wrote the very words to that effect...
Now, the possible influences on boreholes might lead to inferred trends in GST that are
different from those in  SAT is a different one. A number of independent recently published
papers by (Beltrami et al; Stiglitz et al; Mann and Schmidt) and others have demonstrated
that there should be expectations for significant differences between past SAT (what we
care about) and GST variations (what boreholes in the best case scenario see) due to
snowcover influences, etc. We don't have time to discuss that in this very short piece, so
I tried, as briefly as possible, to cover our bases on this issue, in a way that doesn't
really stir up the pot w/ the borehole folks...
I'm interested in any further thoughts on the above,
mike
At 12:38 PM 10/9/03 -0400, Tom Crowley wrote:
Hi, I don't understand why we cannot cite the borehole data for the MWP - that in a
sense is the only legitimate data set that shows a ~1 C cooling from the MWP to the LIA
- forget the deforestation problem for the moment, that is later in time -
if the borehole data for the MWP are legitimate then there is still a case for
concluding that the MWP was significantly warmer than the LIA
tom
Thanks Phil,
a few brief responses and inquiries below...
cheers,
mike
At 04:17 PM 10/9/03 +0100, Phil Jones wrote:
Mike,
Away Oct 11-16, so here are a few comments. A few times the tone could be a little
less
antagonistic. We don't want to inflame things any further. So remove the word laundry.
fair enough. You *should* have seen the first draft I wrote. This is quite toned down
now...
1. With the boreholes do we want to get one of the borehole group to sign up, eg Henry
Pollack?
Would add a lot of weight to the last 500 year argument.
this has merit. unfortunately though I think it might open up a hornets nest of the
author list is not identical to the original list of authors on the Eos article. Other
thoughts on this...
2. On the UHI, there was a paper in a very recent issue of J. Climate by Tom Peterson,
arguing
for the USA that this is non-existent. Issue with UHI is one of large versus local
scale. One
station doesn't influence large-scale averages. All studies which look at the UHI
comprehensively
find very little effect (an order of magnitude smaller than the warming).  Also the
warming
in the 20th century is very similar between the NH and SH and between the land and
ocean
components.
let me see if I can fit one or two sentences in on this and keep the article under the
length.
Also, if we can't estimate temperature histories accurately, then SB can't say it
was
warmer in their MWP period. They believe the 20th century instrumental data when they
want to.
yes, one of a large number of amazing contradictions in their reasoning...
3. Keith is away till next week. I doubt we will have the space to do the 'tree issues'
justice.
Best just to say that there are an (equal) number of non tree-based proxy series??
I do think we need to address their spurious description of the putative biological
effects.  Any way that you can get in touch w/ Keith for a response, perhaps just to
this one point? Also, Malcolm might want to comment on the current wording?
4. Ray, Malcolm and Henry Diaz have a Science Perspectives piece coming out in the next
couple of weeks on the MWP/E. This is also relevant.
good!
5. Don't think we will get away with the last paragraph. Whether we want it is an issue
??
Shouldn't we be sticking to the science.
ok, I wasn't sure myself--yet it is a powerful rebuke, and reminds people that the
objection to the validity of their work goes beyond just our article--and that's
important. Does someone want to try to rephrase this paragraph, maybe reducing it to a
couple sentences?
Cheers
Phil
At 21:37 08/10/2003 -0400, Michael E. Mann wrote:
Dear co-authors,
Attached is a draft response, incorporating suggestions Kevin, Tom W, and Michael.  I've
aimed to be as brief as possible, but hard to go much lower than 750 words and still
address all the key issues. 750 words, by the way, is our allotted limit.
Looking forward to any comments. Feel free to send an edited version if you prefer, and
I'll try to assimilate all of the suggested edits and suggestions into a single revised
draft. If you can get comments to me within the next couple days, that would be very
helpful as we're working on a late October deadline for the final version.
Thanks for your continued help,
mike
______________________________________________________________
Professor Michael E. Mann
Department of Environmental Sciences, Clark Hall
University of Virginia
Charlottesville, VA 22903
_______________________________________________________________________
e-mail: mann@virginia.edu   Phone: (434) 924-7770   FAX: (434) 982-2137
[1]
Prof. Phil Jones
Climatic Research Unit        Telephone +44 (0) 1603 592090
School of Environmental Sciences    Fax +44 (0) 1603 507784
University of East Anglia
Norwich                          Email    p.jones@uea.ac.uk
NR4 7TJ
UK
----------------------------------------------------------------------------
_______________________________________________________________________
Professor Michael E. Mann
Department of Environmental Sciences, Clark Hall
University of Virginia
Charlottesville, VA 22903
_______________________________________________________________________
e-mail: mann@virginia.edu   Phone: (434) 924-7770   FAX: (434) 982-2137
[2]
--
Thomas J. Crowley
Nicholas Professor of Earth Systems Science
Dept. of Earth and Ocean Sciences
Nicholas School of the Environment and Earth Sciences
Box 90227
103  Old Chem Building Duke University
Durham, NC  27708
tcrowley@duke.edu
919-681-8228
919-684-5833  fax
_______________________________________________________________________
Professor Michael E. Mann
Department of Environmental Sciences, Clark Hall
University of Virginia
Charlottesville, VA 22903
_______________________________________________________________________
e-mail: mann@virginia.edu   Phone: (434) 924-7770   FAX: (434) 982-2137
[3]
References
1.
2.
3.
4.


Jan,
Did you finally get the raw ring-width data from Malcolm? Does Keith
know about this? He asked Malcolm for the data as well, but did not
receive a reply as far as I know.
Ed
>Dear Malcom
>
>thank you for the series of mails and attachements! I just came back
>into office (and I am already close to leave for another fieldtrip
>next week), and had no time yet to look in all the files you sent
>me. As soon as I get an overview of what you sent, I will keep you
>informed.
>
>About the Central Asian data, I am just putting another draft
>together also describing some of the new data Kerstin Treydte (who
>is now in our team) sampled. Kerstin herself started working on a
>bigger analysis including her new ring width and stable isotope data
>(she processed 1000-yr. records of carbon and oxygen stable
>isotopes). This will be the major paper of her PhD, and once this
>paper is accepted, we are intending to release data to the ITRDB.
>Will keep you posted.
>
>Thank you again and take care
>Jan
>
>
>
>
>
>>Dear Jan - did you get the e-mail I sent on September 22? It may have caused
>>problems, because there were 10 attachemnts. In fact, I include
>>some that were
>>missed with this message. In addition, you should be able to get
>>the *.rwl files
>>for the 27 western chronologies usedin Mann, Bradley, Hughes 1998 at the
>>following web location:
>>~fenbiao/For_Jan_27rwl/
>>Please let me know if you experience any problems with this.
>>I also omitted some of the attachments from the earlier message. THey should
>>be attached to this one. Good luck! Malcolm
>>
>>------- Forwarded message follows -------
>>From:         	Malcolm Hughes
>>To:           	esper@wsl.ch
>>Subject:      	data
>>Copies to:    	fenbiao@ltrr.arizona.edu
>>Date sent:    	Mon, 22 Sep 2003 17:30:24 -0700
>>
>>Dear Jan - I have recently started to clear up all outstanding
>>business related to the next analysis by Mike Mann, Ray Bradley, et
>>al., and found, to my horror, that I had not replied to your e-mail of
>>last April 8 (copy at end of this message).   In response to our
>>request for access to the data on which your 2000 and 2002 papers were
>>based, you indicated that you would need to check with a colleague at
>>WSL. Have you been able to do this, and if so, what is the result?
>>Obviously we are keen to include all  important data already in the
>>peer reviewed literature, such as yours,  in our analyses. You also
>>requested "the raw measurements of (y)our sequoia data and the western
>>conifer data used in the Mann et al 1998, 1999 papers". 1) data used
>>in Mann et al 1998 - these are all listed in the Nature on-line
>>supplementary materials (attached), and were all from the ITRDB, so
>>they may be downloaded from there. The same list is also attached. We
>>think we can find theraw data  (the *.rwl files) and send them to you
>>if you would like - please let me know. 2)  The western conifer data
>>used in MBH 99 are a subset of these, as indicated in another set of
>>attached MS-Excel files. These are a little bit repetitive, but
>>contain the following particularly useful information for these 27
>>longer chronologies: vchron11000 contains, inter alia, the ITRDB ID,
>>species code, first year, last year, collector's name
>>
>>vchron41000 contains the ITRDB ID, then the first and last
>>years with 5, 10, etc samples
>>
>>vchron81000 contains the ID, etc and then in the following
>>cols: V mn sensitivity W chronology autocorrelation, AE
>>number of series, AG mean correlation of series with
>>chronology AH mean series autocorrelation, AI series mean
>>length, series median segment length.
>>Please remember that this set ranges from lower forest
>>border to upper forest border, so that various mixtures from
>>all precip to precip plus temp locally apply.
>>
>>As I recently told Keith Briffa, you should be aware that it
>>would be completely unjustified to assume that the first
>>measured ring was anywhere near the pith in many of these
>>sites, especially as you go back in time, where the
>>chronologies are based on remnants that have weathered on
>>the inside and the outside. For this, and related, reasons, it
>>would also be completely unjustified to assume any
>>constant, or small, distance in years of the first measured
>>rings from pith. That is, I can see no way of making a
>>remotely reliable estimate of cambial age in the vast
>>majority of these samples. I am sitting on  the
>>bones of a manuscript in which I had someone spend
>>several months checking many hundreds of bristlecone and
>>similar cross-sections and cores in our store. They found
>>only a few dozen - less than 10%, where either pith was
>>present, or the innermost ring could reasonably be described
>>as 'near pith'. If you have seen these stripbark montane 5-
>>needle pines, and ever tried to core them, you will
>>understand why. A further problem arises from the
>>observation that radial increment may increase rather
>>dramatically in the period after most of the bark dies back,
>>but of course we don't know when that was. Andy Bunn at
>>Montana State University has, I think, a manuscript in
>>preparation of review on this. I have a manuscript in
>>preparation  where we restandardized many of these series
>>in the following  way  -
>>identify the long, flat part of the sample ringwidth curve
>>(i.e. remove the 'grand period of growth', if present) and
>>then fit a straight line of no or negative slope.
>>3) I attach *rwl and chronology files from three sequoia sites (those
>>referred to by Hughes and Brown, 1992 Drought frequency in central
>>California since 101 B.C. recorded in giant sequoia tree rings.
>>Climate Dynamics, 6, 161-167 ) Please note the reasons given for the
>>rather strong standardization used (explained in text) and for the
>>splitting of the Mountain Home samples at AD 1297 (this explains my
>>sending you 4 of each kind of file, even though there were only three
>>sites in this case).  We do not have pith dates for these samples, but
>>it is  important to note the following caution - most of the radials
>>and cross- sections were from stumps, where we found that very slow
>>growth near the pith was often an indicator of great age. This of
>>course tells us that trees destined to be very  old were often
>>suppressed for many years in their early life (but not all of them).
>>The tricky part comes from the observation that, although we could see
>>slow growth on the top of the stump near the pith, the wood was often
>>in too poor a state of presevation there to date and measure.
>>Therefore, do not assume that the first ring measured was anywhere
>>near pith - it could easily be off by centuries. There is a *.crn and
>>*.rwl for each of the four chronologies. Gfo is Giant Forest, CSX is
>>Camp Six, and MH is Mountain Home, split into MH1 and MH 2 as
>>indicated above. I'd be interested to know how you get on with this.
>>Cheers, Malcolm . .
>>  ----- Forwarded message from Jan Esper
-----
>>>      Date: Tue, 8 Apr 2003 16:15:35 +0200
>>>      From: Jan Esper
>>>  Reply-To: Jan Esper
>>>   Subject: Re: from Malcolm Hughes
>>>        To: fenbiao@ltrr.arizona.edu
>>>
>>>  Dear Fenbiao and Malcom
>>>
>>>  Since I got funding from the Swiss Science Foundation to do some
>>>  similar research, I really like the idea to share our tree ring
>>>  data. However, I have to discuss this again with Kerstin Treydte who
>>>  now started to work at the WSL and is running a re-analysis
>>>  (including new samplings) for western central Asia.
>>>
>>>  In principle, would it be possible to receive the raw measurements
>>>  of your Sequoia data and the western conifer data used in the Mann
>>>  et al. 1998, 1999 papers?
>>>
>>>  What do you think?
>>>
>>>  Take care
>>>  Jan
>>>
>>>  CC
>>>  K Treydte
>>>  D Frank
>>>
>>>  >Dear Jan,
>>>  >You may be familiar with our earlier attempts at very large scale
>>>  multi-proxy
>>>  >reconstruction of certain aspects of climate, (for example, Mann,
>>>  >Bradley
>>>  and
>>>  >Hughes, 1998, Nature, 392, 779-787). This work was possible because
>>>  >many colleagues made their data available. We are now assembling an
>>>  >updated and extended dataset for new work along similar lines. We
>>>  >hope to take advantage of data that were not available five years
>>>  >ago, and to use improved methods in our analyses.
>>>  >
>>>  >Would you be willing to permit us to use the
>>>  >(chronologies/reconstruction?) reported in your paper (s) listed
>>  > >below?
>>>  >
>>>  >Esper J. (2000). Long-term tree-ring variations in Juniperus at the
>>>  >upper timber-line in karakorum (Pakistan). Holocene 10 (2),
>>>  >253-260.
>>>  >
>>>  >Esper J., Schweingruber F.H., Winiger M. (2002). 1300 years of
>>>  >climatic history for western central Asia inferred from tree-rings.
>>>  >Holocene 12 (3),
>>>  267-277.
>>>  >
>>>  >We are particularly interested in (1) the ring-width series of
>>>  >Juniperus excelsa M. Bieb and Juniperus turkestanica Kom. From 6
>>>  >different sites in
>>>  the
>>>  >Hunza-karakorrum;
>>>  >(2) 20 individual sites ranging from the lower to upper local
>>>  >timber-lines
>>>  in
>>>  >the Northwest karakorum of Pakistan and the Southern Tien Shan of
>>>  Kirghizia.
>>>  >
>>>  >If at all possible, we would prefer to receive tree-ring data as
>>>  >both raw
>>>  data
>>>  >(individual unmodified measurement series for all samples used) and
>>>  >your
>>>  final
>>>  >chronologies used in the publication.
>>>  >
>>>  >If you are willing to share your data for the purposes of our
>>>  >analyses, but
>>>  do
>>>  >not
>>>  >wish them to be passed on to anyone else by us, please tell us, and
>>>  >we will mark the data accordingly in our database. If data have
>>>  >been marked as not being publicly available, we will pass on any
>>>  >requests for them to you.
>>>  >
>>>  >Please reply to Dr. Fenbiao Ni’s email address (this one). Many
>>>  >thanks.
>>>  >
>>>  >Sincerely,
>>>  >Malcolm K. Hughes
>>>  >(team: Michael E. Mann, Ray Bradley, Malcolm Hughes, Scott
>>>  >Rutherford,
>>>  Fenbiao
>>>  >Ni)
>>>  >
>>>  >Malcolm Hughes
>>>  >Professor of Dendrochronology
>>>  >Laboratory of Tree-Ring Research
>>>  >University of Arizona
>>>  >Tucson, AZ 85721
>>>  >520-621-6470
>>>  >fax 520-621-8229
>>>
>>>
>>>  --
>>>  Dr. Jan Esper
>>>  Swiss Federal Research Institute WSL
>>>  Zuercherstrasse 111, 8903 Birmensdorf
>>>  Switzerland
>>>  Phone: +41-1-739 2510
>>>  Fax:     +41-1-739 2215
>>>  Email:   esper@wsl.ch
>>>
>>>  ----- End forwarded message -----
>>>
>>>
>>>
>>
>>
>>
>>
>>----- End forwarded message -----
>>
>>
>>
>>
>>
>>Attachments:
>>   D:\Projects\Bradley and Mann\Newest June 9 1997\westernforjan.xls
>>   D:\Projects\Bradley and Mann\Nature figures\naturesupmat.doc
>>   D:\Projects\SEQUOIA\for esper\csx.rwl D:\Projects\SEQUOIA\for
>>   esper\csxars.crn D:\Projects\SEQUOIA\for esper\gfo.rwl
>>   D:\Projects\SEQUOIA\for esper\gfoars.crn D:\Projects\SEQUOIA\for
>>   esper\mhf1.rwl D:\Projects\SEQUOIA\for esper\mhf2.rwl
>>   D:\Projects\SEQUOIA\for esper\MHF2ARS.CRN D:\Projects\SEQUOIA\for
>>   esper\MHF1ARS.CRN
>>------- End of forwarded message -------Malcolm
>>Hughes
>>Professor of Dendrochronology
>>Laboratory of Tree-Ring Research
>>University of Arizona
>>Tucson, AZ 85721
>>520-621-6470
>>fax 520-621-8229
>
>
>--
>Dr. Jan Esper
>Swiss Federal Research Institute WSL
>Zuercherstrasse 111, 8903 Birmensdorf
>Switzerland
>Phone: +41-1-739 2510
>Fax:     +41-1-739 2215
>Email:   esper@wsl.ch
--
==================================
Dr. Edward R. Cook
Doherty Senior Scholar and
Director, Tree-Ring Laboratory
Lamont-Doherty Earth Observatory
Palisades, New York 10964  USA
Email:	drdendro@ldeo.columbia.edu
Phone:	845-365-8618
Fax:	845-365-8152
==================================


At 20:02 09/10/2003, Michael E. Mann wrote:
Dear All,
I like all of Kevin's changes. Please work with his version as a template for any
additional suggested changes. I'll incorporate the additional comments received from
Phil and Tom W and others afterwards...
thanks,
mike
Dear Mike and co-authors,
I've now had a chance to go through the drafts and comments etc.  Working from Kevin's
version, here are some suggestions to consider:
(1) Are you sure that what we saw is the final version of S03, after any EOS editing,
etc.?  Wouldn't want any of the S03 quotes used here to get changed if they had to edit to
reduce the length of their piece!
(2) Suggested re-ordering of the end of point (1): 'it holds in some cases for tree-ring
density measurements at higher latitudes, but rarely for annual ring widths.'
(3) Suggested re-wording near start of point (2):  '"clearly shows temperatures in the MWP
that are as high as those in the 20th century" is misleading because it is true for only
the early 20th century.  The hemispheric warmth of the late 20th century is anomalous in a
long-term context.' (with underlining of either 'late' or 'is' for emphasis).  Of course,
this suggestion needs to be checked carefully (e.g., is it only the 'early' 20th century
that is exceeded by some earlier temperatures?).  But it is an important change because it
is not actually 'false' or 'untrue' if some part of the 20th century was exceeded earlier -
they don't specify which part, so their statement is (probably deliberately) vague rather
than wrong.  The above suggestion simply points this out.
(4) Related to this comment, is the question of whether the actual reconstruction (not
instrumental observations) in the late 20th century exceeds all reconstructed values
(central estimates) prior to the 20th century.  My copy of Mann and Jones (2003) has poor
quality figures, so this is hard for me to tell.  It appears that it might be true, but
only right at the end - i.e. the 1980 value of the filtered series.  If it is really only
at the end, and a 40-year smoothing filter is used, then I would be concerned about this
statement appearing in the response if it depends upon applying the filter right up to the
end of the record.  Doing so requires some assumption about values past the end of the
series.  This in itself is problematic, but especially so if the assumption were that the
trend was extrapolated to produce values for input to the filter.  Of course, if the
straight 40-year mean from 1941-1980 of the reconstruction exceeds all other 40-year means
of the reconstruction, then I'd be happy with the statement.
(5) I don't like point (3) on the boreholes.  It relies on the "optimal" borehole series of
Mann et al. (2003), a result that I have some concerns about and which is being used here
to imply less uncertainty than really exists over this issue.  In the EOS paper we included
this and the "non-optimal" gridded borehole series, so we were leaving open some
uncertainty.  I'm not saying that I prefer/believe the Huang et al. series either, since I
agree that extracting the temperature signal from the borehole data is very difficult.  I
just don't like to imply it has been solved when it hasn't.
(6) Can we provide a supporting reference for the statement in point (4) about land use
changes leading to an overall cooling?
(7) I like the final paragraph as it is, possibly dropping the last "We feel it is time to
move on" line.
Cheers
Tim


X-Sender: esper@mail.wsl.ch
Date: Mon, 13 Oct 2003 15:21:03 +0200
To: Keith Briffa
From: Jan Esper
Subject: minor explosion
Cc: Wilson Rob
Hi Keith
thank you for the message and the comments to the Siberia draft. We are intending to
finalize a draft when Rob is coming over and we go on a sampling trip to the Bavarian
Forest and E-Germany. We will then also discuss of data-overlap issue again and might
include some extra figure with our record re-calculated (without Tornetraesk and Polar
Ural).
However, I (Jan) an not sure that we should have another figure with only the Mann and
the (reduced) Esper series. Second, it seems that Mann used the density records from
these two sites only (not ring width). Lets see.
We would really like to send you the final draft, and ask you to become the fourth
author? We ask this not only because of the "minor explosion" that might happen, but
also because some of the arguments in the draft were made earlier by you anyway. What do
you think?
Take care
Jan and Dave
CC
R Wilson
Jan
with respect to the overlap problem we could agree to differ for now -I think the
problem is much more in the earlier period anyway but I suggest you go ahead and submit
it anyway. There are some minor wording points but nothing that affects the meaning. You
know that in my opinion the recent similarity in the records is driven by instrumental
data inclusion (or calibration against instrumental data) and that Mann's earlier data
are strongly biased towards summer and northern land signals. I think you will start a
minor explosion - but that is what science needs .
I looked at your tree-line data and thought them very interesting. In my opinion the way
you directed the interpretation was what drew your criticisms . For a climate journal
you should have been pointing out the complicated regional responses (to the temperature
record) rather than trying to state a simple overall response. The data are clearly
important and you should have no trouble publishing them if you rethink the approach to
the description (no work needed). I think Boreas or Arctic and Alpine Res. are better
targets though. I enjoyed  the discussions also and it is frustrating not to be able to
get up to speed with your other projects. I will get back to you when I have looked more
at the idea of the big review paper.
the very best to you and all
Keith
At 09:55 AM 10/8/03 +0200, Jan Esper wrote:
Hi Keith
with respect to our EOS draft, I am still thinking about the data overlap argument you
made.
1. I still believe that the overlap is not that significant, and that the significance
is changing dramatically with time (less in more recent centuries).
2. With respect to the aim of the paper, we do NOT intend to explain the similarity
between the records. We rather address that the recons differ in the lower frequency
domains AND are much more similar in the higher frequency domains. I believe that this
is crucial. (One could also say that we only address the dissimilarity, and the
arguments related to that.)
I appreciated the discussions we had very, very much (especially the one in the night
before the official meeting).
Take care
Jan
CC
D Frank
R Wilson
--
Dr. Jan Esper
Swiss Federal Research Institute WSL
Zuercherstrasse 111, 8903 Birmensdorf
Switzerland
Phone: +41-1-739 2510
Fax:     +41-1-739 2215
Email:   esper@wsl.ch
--
Professor Keith Briffa,
Climatic Research Unit
University of East Anglia
Norwich, NR4 7TJ, U.K.
Phone: +44-1603-593909
Fax: +44-1603-507784
[1]
--
Dr. Jan Esper
Swiss Federal Research Institute WSL
Zuercherstrasse 111, 8903 Birmensdorf
Switzerland
Phone: +41-1-739 2510
Fax:     +41-1-739 2215
Email:   esper@wsl.ch
--
Professor Keith Briffa,
Climatic Research Unit
University of East Anglia
Norwich, NR4 7TJ, U.K.
Phone: +44-1603-593909
Fax: +44-1603-507784
[2]
References
1.
2.
3.


Mike and all
Hi , just back from a trip and only now catching up with important emails. Given
the restricted time and space available to furnish a response to SB comments ,
I offer the following mix of comment and specific wording changes:
I agree that the S+B response is designed to deflect criticism by confusing the issues
rather than answering our points.
In fact they fail to address any of the 3 specific
issues we raised Namely , 1. the need for critical evaluation of proxy inputs , 2. the
need for a consistent assimilation of widespread (dated and well resolved ) records,
3. the essential requirement for objective/quantitative calibration (scaling) of the input
records to allow for assessment of the uncertainties when making
comparisons of different reconstructions and when comparing early with recent
temperatures.
Their own , ill-conceived and largely subjective approach did not take
account of the uncertainties and problems in the use of palaeodata that they chose to
highlight in their opening remarks.
I would be in favour of stating something to this effect at the outset of our response.
Also , as regards the tree-ring bit , I fully concur with  the sense of your text as
regards Section 1, but suggest the following wording (to replace ",rarely for annual
ring widths, and almost entirely at higher latitudes.")
"but in certain high-latitude regions only. Where this is the case , these relatively
recent
(ie post 1950) data are not used in calibrating temperature reconstructions. In many other
(even high-latitude) areas  density or ring-width records display no bias."
In the spirit of healthy debate - I agree with Tim's remarks , warning against presenting a
too
sanguine impression that the borehole debate is closed ( though I do think it is closing!).
I also believe , as you already know, that the use of a recent padding algorithm to extend
smoothed data to the present time, is inappropriate if it assumes the continuation of a
recent
trend. This is likely to confuse , rather than inform, the wider public about the current
climate state .
Finally , I repeat my earlier remarks (made before EOS piece published) that we are missing
an opportunity to say that a warm Medieval period per se is not a refutation of
anthropogenic
warming , {as its absence is no proof}, if we do not understand the role of specific
forcings (natural
and anthropogenic) that influenced medieval and current climates.
Cheers
Keith
At 12:48 PM 10/9/03 -0600, Kevin Trenberth wrote:
Hi all
Here are my suggested changes: toned down in several places.  Tracking turned on
Kevin
Michael E. Mann wrote:
Dear co-authors,
Attached is a draft response, incorporating suggestions Kevin, Tom W, and Michael.  I've
aimed to be as brief as possible, but hard to go much lower than 750 words and still
address all the key issues. 750 words, by the way, is our allotted limit.
Looking forward to any comments. Feel free to send an edited version if you prefer, and
I'll try to assimilate all of the suggested edits and suggestions into a single revised
draft. If you can get comments to me within the next couple days, that would be very
helpful as we're working on a late October deadline for the final version.
Thanks for your continued help,
mike
______________________________________________________________
Professor Michael E. Mann
Department of Environmental Sciences, Clark Hall
University of Virginia
Charlottesville, VA 22903
_______________________________________________________________________
e-mail: [1]mann@virginia.edu  Phone: (434) 924-7770   FAX: (434) 982-2137
[2]
--
****************
Kevin E. Trenberth                              e-mail: [3]trenbert@ucar.edu
Climate Analysis Section, NCAR                  [4]www.cgd.ucar.edu/cas/
P. O. Box 3000,                                 (303) 497 1318
Boulder, CO 80307                               (303) 497 1333 (fax)
Street address: 1850 Table Mesa Drive, Boulder, CO  80303
--
Professor Keith Briffa,
Climatic Research Unit
University of East Anglia
Norwich, NR4 7TJ, U.K.
Phone: +44-1603-593909
Fax: +44-1603-507784
[5]
References
1. mailto:mann@virginia.edu%A0
2.
3. mailto:trenbert@ucar.edu
4.
5.
6.


thanks Caspar,
I agree--its important to emphasize this point, and I'm glad you recognized that we were
underplaying it...
mike
At 10:25 AM 10/14/2003 -0600, Caspar Ammann wrote:
Mike,
looks good to me. It is one of these points where they can persuade journalists that
they are 'correct' and it actually got into newspapers and finally to the senate floor
this way. The more we are able to explain why the first half of the 20th century warmed
up naturally, the more confidence we get on the detection of the anthropogenic signal
afterwards.
Caspar
Michael E. Mann wrote:
Dear All,
In response to Caspar's suggestion, which I agree with,  I propose rephrasing item "2"
as follows:
2) The statement by S03 that the Mann and Jones [2003] reconstruction "clearly shows
temperatures in the MWP that are as high as those in the 20th century" is misleading if
not false. M03 emphasize that it is the  late, and not the early or mid 20th century
warmth, that is outside the range of past variability. Mann and Jones emphasize
conclusions for the Northern Hemisphere, noting that those for the Southern Hemisphere
(and globe) are  indeterminate due to a paucity of southern hemisphere data. Consistent
with M03, they conclude that, late 20th century Northern Hemisphere mean temperatures
are anomalous in a long-term (nearly two millennium) context.
Any comments?
Thanks,
mike
Delivered-To: [1]mem6u@virginia.edu
Date: Tue, 14 Oct 2003 09:18:37 -0600
From: Caspar Ammann [2]
Organization: NCAR
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.4) Gecko/20030624
Netscape/7.1 (ax)
X-Accept-Language: en-us, en
To: "Michael E. Mann" [3]
Subject: Re: draft
Hi Mike,
it now looks good to me indeed including the new last paragraph following Tom's wording.
The only point I would highlight a little more is in point 2): Maybe it could be stated
that the early part of the 20th century is within the natural range whereas the late
20th century, the main point of the AGU position statement and also in M03, is clearly
outside. Please also add a second 'n' in my name...
Cheers, and thanks for your momentum on this,
Caspar
Michael E. Mann wrote:
Dear All,
I agree with each of Tom W's suggestions. Adopting them, by the way, brings us down to
738 words.
So pending any revised language from Keith/Malcolm in response to Michael O's comment on
paragraph 2, I'm putting out a last call for comments, sign-ons, etc...
Thanks,
mike
At 08:00 AM 10/14/2003 -0600, Tom Wigley wrote:
Some minor points ....
para. 2 -- should it be 'an' ensuing rather than 'the' ensuing?
para. 2 -- I still think 'each' (line 3) is unnecessary
para. 4 -- no comma after '(and globe)'
re boreholes, does the point about comparing late 20th century with a 'much longer
period' 1000 years ago help us? Given that the 1000 years ago data is highly lowpass
filtered, if one *did* have a series with a temporal resolution that allowed a
legitimate comparison, then the likelihood of a warmer interval 1000 years ago must be
higher.
In any event, the time scale issue will not be meaningful to most readers. The key point
is the data reliability/uncertainty. I would just say something like ...
".... taken into account. For times more than 500 years ago, uncertainties in the
borehole reconstructions preclude any useful quantitative comparison."
Finally, I would like the last para. retained, but I suggest shorter wording as ...
".... as indicating that SB03 misinterpreted and misrepresented the paleoclimatological
literature. The controversy ....".
My problem here is twofold. First, they really say nothing directly about 'mainstream
scientific opinion' (except that they clearly disagree with it). At issue is not the
mainstream opinion, but their interpretation of the literature and their illogical
conclusions. Second, they may have misrepresented the results of their work, but we do
not address this issue so it comes here as a non sequitur. In fact, just what such
'misrepresentation' consists of, and why it might be judged as 'misrepresentation' is a
subtle issue. Hence my revision -- which retains the word 'misrepresentation', but in a
different context.
Tom.
+++++++++++++++++++++++++++++++==
Michael E. Mann wrote:
Thanks Tim and Malcolm,
The latest round of suggestions were extremely helpful. I've accepted them w/ a few
minor tweaks (attached). We're at 765 words--I think AGU will let us get away w/ that...
So, comments from others?
Thanks,
mike
At 02:11 PM 10/14/2003 +0100, Tim Osborn wrote:
SO3 argue that borehole data provide a conflicting view of past temperature histories.
To the contrary, the borehole estimates for recent centuries shown in M03 may be
consistent with other estimates, provided consideration is given to statistical
uncertainties, spatial sampling and possible influences on the ground surface [e.g.,
snow cover changes--Beltrami and Kellman, 2003].  It is not meaningful to compare the
late 20th century with a much longer period 1000 years ago [Bradley et al., 2003],
especially given the acknowledged limitations [Pollack et al., 1998] of borehole data.
______________________________________________________________
Professor Michael E. Mann
Department of Environmental Sciences, Clark Hall
University of Virginia
Charlottesville, VA 22903
_______________________________________________________________________
e-mail: [4]mann@virginia.edu   Phone: (434) 924-7770   FAX: (434) 982-2137
[5]
______________________________________________________________
Professor Michael E. Mann
Department of Environmental Sciences, Clark Hall
University of Virginia
Charlottesville, VA 22903
_______________________________________________________________________
e-mail: [6]mann@virginia.edu   Phone: (434) 924-7770   FAX: (434) 982-2137
[7]
--
Caspar M. Ammann
National Center for Atmospheric Research
Climate and Global Dynamics Division - Paleoclimatology
Advanced Study Program
1850 Table Mesa Drive
Boulder, CO 80307-3000
email:
[8]ammann@ucar.edu
tel: 303-497-1705     fax: 303-497-1348
______________________________________________________________
Professor Michael E. Mann
Department of Environmental Sciences, Clark Hall
University of Virginia
Charlottesville, VA 22903
_______________________________________________________________________
e-mail: [9]mann@virginia.edu   Phone: (434) 924-7770   FAX: (434) 982-2137
[10]
--
Caspar M. Ammann
National Center for Atmospheric Research
Climate and Global Dynamics Division - Paleoclimatology
Advanced Study Program
1850 Table Mesa Drive
Boulder, CO 80307-3000
email:
[11]ammann@ucar.edu
tel: 303-497-1705     fax: 303-497-1348
______________________________________________________________
Professor Michael E. Mann
Department of Environmental Sciences, Clark Hall
University of Virginia
Charlottesville, VA 22903
_______________________________________________________________________
e-mail: mann@virginia.edu   Phone: (434) 924-7770   FAX: (434) 982-2137
[12]
References
1. mailto:mem6u@virginia.edu
2. mailto:ammann@ucar.edu
3. mailto:mann@virginia.edu
4. mailto:mann@virginia.edu
5.
6. mailto:mann@virginia.edu
7.
8. mailto:ammann@ucar.edu
9. mailto:mann@virginia.edu
10.
11. mailto:ammann@ucar.edu
12.


Sorry--one more error. The MSE values for "minimum norm" and "minimum roughness" are
switched in the figure legend. Obviously the former is a better fit...
mike
Date: Tue, 14 Oct 2003 17:08:49 -0400
To: Tom Wigley
, Kevin Trenberth
, Keith Briffa
, Phil Jones
, ckfolland@meto.gov.uk,
tkarl@ncdc.noaa.gov, jto@u.arizona.edu, mann@virginia.edu
From: "Michael E. Mann"
Subject: Re: smoothing
Bcc: Scott Rutherford
correction '1)' should read:
'1) minimum norm: sets padded values equal to mean of available data beyond the
available data (often the default constraint in smoothing routines)'
sorry for the confusion,
mike
At 05:05 PM 10/14/2003 -0400, Michael E. Mann wrote:
Dear All,
To those I thought might be interested, I've provided an example for discussion of
smoothing conventions.  Its based on a simple matlab script which I've written (and
attached) that uses any one of 3 possible boundary constraints [minimum norm, minimum
slope, and minimum roughness] on the 'late' end of a time series (it uses the default
'minimum norm' constraint on the 'early' end of the series). Warming: you needs some
matlab toolboxes for this to run...
The routines uses a simple butterworth lowpass filter, and applies the 3 lowest order
constraints in the following way:
1) minimum norm: sets mean equal to zero beyond the available data (often the default
constraint in smoothing routines)
2) minimum slope: reflects the data in x (but not y) after the last available data
point. This tends to impose a local minimum or maximum at the edge of the data.
3) minimum roughness: reflects the data in both x and y (the latter w.r.t. to the y
value of the last available data point) after the last available data point. This tends
to impose a point of inflection at the edge of the data---this is most likely to
preserve a trend late in the series and is mathematically similar, though not identical,
to the more ad hoc approach of padding the series with a continuation of the trend over
the past 1/2 filter width.
The routine returns the mean square error of the smooth with respect to the raw data. It
is reasonable to argue that the minimum mse solution is the preferable one.  In the
particular example I have chosen (attached), a 40 year lowpass filtering of the CRU NH
annual mean series 1856-2003, the preference is indicated for the "minimum roughness"
solution as indicated in the plot (though the minimum slope solution is a close 2nd)...
By the way, you may notice that the smooth is effected beyond a single filter width of
the boundary. That's because of spectral leakage, which is unavoidable (though minimized
by e.g. multiple-taper methods).
I'm hoping this provides some food for thought/discussion, esp. for purposes of IPCC...
mike
______________________________________________________________
Professor Michael E. Mann
Department of Environmental Sciences, Clark Hall
University of Virginia
Charlottesville, VA 22903
_______________________________________________________________________
e-mail: mann@virginia.edu   Phone: (434) 924-7770   FAX: (434) 982-2137
[1]
______________________________________________________________
Professor Michael E. Mann
Department of Environmental Sciences, Clark Hall
University of Virginia
Charlottesville, VA 22903
_______________________________________________________________________
e-mail: mann@virginia.edu   Phone: (434) 924-7770   FAX: (434) 982-2137
[2]
______________________________________________________________
Professor Michael E. Mann
Department of Environmental Sciences, Clark Hall
University of Virginia
Charlottesville, VA 22903
_______________________________________________________________________
e-mail: mann@virginia.edu   Phone: (434) 924-7770   FAX: (434) 982-2137
[3]
References
1.
2.
3.


Dear All,
Thought you would be interested in this exchange, which John Holdren of Harvard has been
kind enough to pass along...
mike
Delivered-To: mem6u@virginia.edu
X-Sender: jholdren@camail2.harvard.edu
X-Mailer: QUALCOMM Windows Eudora Version 5.0.2
Date: Thu, 16 Oct 2003 13:53:08 -0400
To: "Michael Mann"
, "Tom Wigley"
From: "John P. Holdren"
Subject: Correspondence on Harvard Crimson coverage of Soon / Baliunas
views on climate
Michael and Tom --
I'm forwarding for your entertainment an exchange that followed from my being quoted in
the Harvard Crimson to the effect that you and your colleagues are right and my
"Harvard" colleagues Soon and Baliunas are wrong about what the evidence shows
concerning surface temperatures over the past millennium.   The cover note to faculty
and postdocs in a regular Wednesday breakfast discussion group on environmental science
and public policy in Harvard's Department of Earth and Planetary Sciences is more or
less self-explanatory.
Best regards,
John
Date: Thu, 16 Oct 2003 11:02:24 -0400
To: schrag@eps.harvard.edu, oconnell@eps.harvard.edu, holland@eps.harvard.edu,
pearson@eps.harvard.edu, eli@eps.harvard.edu, ingalls@eps.harvard.edu,
mlm@eps.harvard.edu, avan@fas.harvard.edu, moyer@huarp.harvard.edu,
poussart@fas.harvard.edu, jshaman@fas.harvard.edu, sivan@fas.harvard.edu,
bec@io.harvard.edu, saleska@fas.harvard.edu
From: "John P. Holdren"
Subject: For the EPS Wednesday breakfast group:  Correspondence on Harvard Crimson
coverage of Soon / Baliunas views on climate
Cc: jeremy_bloxham@harvard.edu, william_clark@harvard.edu,
patricia_mclaughlin@harvard.edu,
Bcc:
Colleagues--
I append here an e-mail correspondence I have engaged in over the past few days trying
to educate a Soon/Baliunas supporter who originally wrote to me asking how I could think
that Soon and Baliunas are wrong and Mann et al. are right (a view attributed to me,
correctly, in the Harvard Crimson).  This individual apparently runs a web site on which
he had been touting the Soon/Baliunas position.
While it is sometimes a mistake to get into these exchanges (because one's interlocutor
turns out to be ineducable and/or just looking for a quote to reproduce out of context
in an attempt to embarrass you), there was something about this guy's formulations that
made me think, at each round, that it might be worth responding.   In the end, a couple
of colleagues with whom I have shared this exchange already have suggested that its
content would be of interest to others, and so I am sending it to our "environmental
science and policy breakfast" list for your entertainment and, possibly, future
breakfast discussion.
The items in the correspondence are arranged below in chronological order, so that it
can be read straight through, top to bottom.
Best,
John
At 09:43 PM 9/12/2003 -0400, you wrote:
Dr. Holdren:
In a recent Crimson story on the work of Soon and Baliunas, who have written for my
website [1]www.techcentralstation.com, you are quoted as saying:
My impression is that the critics are right. It s unfortunate that so much attention is
paid to a flawed analysis, but that s what happens when something happens to support the
political climate in Washington.
Do you feel the same way about the work of Mann et. al.?  If not why not?
Best,
Nick
Nick Schulz
Editor
TCS
1-800-619-5258
From: John P. Holdren [[2]mailto:john_holdren@harvard.edu]
Sent: Monday, October 13, 2003 11:06 AM
To: Nick Schulz
Subject: Harvard Crimson coverage of Soon / Baliunas controversy
Dear Nick Schultz --
I am sorry for the long delay in this response to your note of September 12.  I have
been swamped with other commitments.
As you no doubt have anticipated, I do not put Mann et al. in the same category with
Soon and Baliunas.
If you seriously want to know "Why not?", here are three ways one might arrive at what I
regard as the right conclusion:
(1)  For those with the background and patience to penetrate the scientific arguments,
the conclusion that Mann et al. are right and Soon and Baliunas are wrong follows from
reading carefully the relevant Soon / Baliunas paper and the Mann et al. response to it:
W. Soon and S. Baliunas, "Proxy climatic and environmental changes of the past 1000
years", Climate Research, vol. 23, pp 89ff, 2003.
M. Mann, C. Amman, R. Bradley, K. Briffa, P. Jones, T. Osborn, T. Crowley, M. Hughes, M.
Oppenheimer, J. Overpeck, S. Rutherford, K. Trenberth, and T. Wigley, "On past
temperatures and anomalous late-20th century warmth", EOS, vol 84, no. 27, pp 256ff, 8
July 2003.
This is the approach I took.  Soon and Baliunas are demolished in this comparison.
(2) Those lacking the background and/or patience to penetrate the two papers, and
seriously wanting to know who is more likely to be right, have the option of asking
somebody who does possess these characteristics -- preferably somebody outside the
handful of ideologically committed and/or oil-industry-linked professional
climate-change skeptics -- to evaluate the controversy for them.   Better yet, one could
poll a number of such people.  They can easily be found by checking the web pages of
earth sciences, atmospheric sciences, and environmental sciences departments at any
number of major universities.
(3)  The least satisfactory approach, for those not qualified for (1) and lacking the
time or initiative for (2), would be to learn what one can about the qualifications
(including publications records) and reputations, in the field in question, of the
authors on the two sides.   Doing this would reveal that Soon and Baliunas are,
essentially, amateurs in the interpretation of historical and paleoclimatological
records of climate change, while the Mann et al. authors include several of the most
published and most distinguished people in the world in this field.    Such an
investigation would also reveal that Dr. Baliunas' reputation in this field suffered
considerable damage a few years back, when she put her name on an incompetent critique
of mainstream climate science that was never published anywhere respectable but was
circulated by the tens of thousands, in a format mimicking that of a reprint from the
Proceedings of the National Academy of Sciences, in pursuit of signatures on a petition
claiming that the mainstream findings were wrong.
Of course, the third approach is the least satisfactory because it can be dangerous to
assume that the more distinguished people are always right.  Occasionally, it turns out
that the opposite is true.   That is one of several good reasons that it pays to try to
penetrate the arguments, if one can, or to poll others who have tried to do so.   But in
cases where one is not able or willing to do either of these things -- and where one is
able to discover that the imbalance of experience and reputation on the two sides of the
issue is as lopsided as here -- one ought at least to recognize that the odds strongly
favor the proposition that the more experienced and reputable people are right.   If one
were a policy maker, to bet the public welfare on the long odds of the opposite being
true would be foolhardy.
Sincerely,
John Holdren
PS:  I have provided this response to your query as a personal communication, not as
fodder for selective excerpting on your web site or elsewhere.  If you do decide that
you would like to propagate my views on this matter more widely,  I ask that you convey
my response in its entirety.
At 11:16 AM 10/13/2003 -0400, you wrote:
I have the patience but, by your definition certainly, not the background, so I suppose
it s not surprising I came to a different conclusion.  I guess my problem concerns what
lawyers call the burden of proof.  The burden weighs heavily much more heavily, given
the claims on Mann et.al. than it does on Soon/Baliunas.  Would you agree?
Falsifiability for the claims of Mann et. al. requires but a few examples, does it
not?   Soon/Baliunas make claims that have no such burden.  Isn t that correct?
Best,
Nick
From: John P. Holdren [[3]mailto:john_holdren@harvard.edu]
Sent: Tuesday, October 14, 2003 5:54 PM
To: Nick Schulz
Subject: RE: Harvard Crimson coverage of Soon / Baliunas controversy
Nick--
Yes, I can see how it might seem that, in principle, those who are arguing for a strong
and sweeping proposition (such as that "the current period is the warmest in the last
1000 years") must meet a heavy burden of proof, and that, because even one convincing
counter-example shoots the proposition down, the burden that must be borne by the
critics is somehow lighter.   But, in practice, burden of proof is an evolving thing --
it evolves as the amount of evidence relevant to a particular proposition grows.
To choose an extreme example, consider the first and second laws of thermodynamics.
Both of these are "empirical" laws.   Our confidence in them is based entirely on
observation;   neither one can be "proven" from more fundamental laws.   Both are very
sweeping.   The first law says that energy is conserved in all physical processes.   The
second law says that entropy increases in all physical processes.   So, is the burden of
proof heavier on somebody who asserts that these laws are correct, or on somebody who
claims to have found an exception to one or both of them?   Clearly, in this case, the
burden is heavier on somebody who asserts an exception.   This is in part because the
two laws have survived every such challenge in the past.   No exception to either has
ever been documented.   Every alleged exception has turned out to be traceable to a
mistake of some kind.   This burden on those claiming to have found an exception is so
strong that the US Patent Office takes the position, which has been upheld in court,
that any patent application for an invention that violates either law can be rejected
summarily, without any further analysis of the details.
Of course, I am not asserting that the claim we are now in the warmest period in a
millennium is in the same league with the laws of thermodynamics.  I used the latter
only to illustrate the key point that where the burden is heaviest depends on the state
of prior evidence and analysis on the point in question -- not simply on whether a
proposition is sweeping or narrow.
In the case actually at hand, Mann et al. are careful in the nature of their claim.
They write along the lines of "A number of reconstructions of large-scale temperature
changes support the conclusion" that the current period is the warmest in the last
millennium.   And they write that the claims of Baliunas et al. are "inconsistent with
the preponderance of scientific evidence".    They are not saying that no shred of
evidence to the contrary has ever been produced, but rather that analysis of the
available evidence as a whole tends to support their conclusion.
This is often the case in science.   That is, there are often "outlier" data points or
apparent contradictions that are not yet adequately explained, but still are not given
much weight by most of the scientists working on a particular issue if a strong
preponderance of evidence points the other way.  This is because the scientists judge it
to be more probable that the outlier data point or apparent contradiction will
ultimately turn out to be explainable as a mistake, or otherwise explainable in a way
that is consistent with the preponderance of evidence, than that it will turn out that
the preponderance of evidence is wrong or is being misinterpreted.  Indeed, apparent
contradictions with a preponderance of evidence are FAR more often due to measurement
error or analysis error than to real contradiction with what the preponderance
indicates.
A key point, then, is that somebody with a PhD claiming to have identified a
counterexample does not establish that those offering a general proposition have failed
in their burden of proof.   The counterexample itself must pass muster as both valid in
itself and sufficient, in the generality of its implications, to invalidate the
proposition.
In the case at hand,  it is not even a matter of an "outlier" point or other seeming
contradiction that has not yet been explained.  Mann et al. have explained in detail why
the supposed contrary evidence offered by Baliunas et al. does NOT constitute a
counterexample.  To those with some knowledge and experience in studies of this kind,
the refutation by Mann et al is completely convincing.
Sincerely,
John Holdren
At 08:08 AM 10/15/2003 -0400, you wrote:
Dr. Holdren:
Thank you for your thoughtful reply. I genuinely appreciate you taking the time.
You are quite right about the laws of thermodynamics.  And you are quite right that Mann
et al is not in the same league as those laws and that s not to take anything from their
basic research.
You write to those with knowledge and experience in studies of this kind, the refutation
by Mann et all is completely convincing.   Since I do not have what you would consider
the requisite knowledge or experience, I can t speak to that.  I ve read the Mann papers
and the Baliunas Soon paper and the Mann rebuttal and find Mann s claims based on his
research extravagant and beyond what he can legitimately claim to know. That said, I m
willing to believe it is because I don t have the tools necessary to understand.
But if you will indulge a lay person with some knowledge of the matter, perhaps you
could clear up a thing or two.
Part of the confusion over Mann et al it seems to me has to do not with the research
itself but with the extravagance of the claims they make based on their research.
And yet you write: Mann et al. are careful in the nature of their claim.   They write
along the lines of A number of reconstructions of large-scale temperature changes
support the conclusion that the current period is the warmest in the last millennium.
And they write that the claims of Baliunas et al. are inconsistent with the
preponderance of scientific evidence .
That makes it seem as if Mann s not claiming anything particularly extraordinary based
on his research.
But Mann claimed in the NYTimes in 1998 that in their Nature study from that year Our
conclusion was that the warming of the past few decades appears to be closely tied to
emission of greenhouse gases by humans and not any of the natural factors."  Does that
seem to be careful in the nature of a claim?  Respected scientists like Tom Quigley
responded at the time by saying "I think there's a limit to how far you can ever go." As
for using proxy data to detect a man-made greenhouse effect, he said, "I don't think
we're ever going to get to the point where we're going to be totally convincing." These
are two scientists who would agree on the preponderance of evidence and yet they make
different claims about what that preponderance means.  There are lots of respected
climatologists who would say Mann has insufficient scientific basis to make that claim.
Would you agree?  The Soon Baliunas research is relevant to that element of the debate
what the preponderance of evidence enables us to claim within reason.  To that end, I
don t think claims of Soon Baliunas are inconsistent with the preponderance of
scientific evidence.
I ll close by saying I m willing to admit that, as someone lacking a PhD, I could be
punching above my weight.  But I will ask you a different but related question How much
hope is there for reaching reasonable public policy decisions that affect the lives of
millions if the science upon which those decisions must be made is said to be by
definition beyond the reach of those people?
All best,
Nick
Date: Thu, 16 Oct 2003 08:46:23 -0400
To: "Nick Schulz"
From: "John P. Holdren"
Subject: RE: Harvard Crimson coverage of Soon / Baliunas controversy
Nick--
You ask good questions.  I believe the thoughtfulness of your questions and the progress
I believe we are making in this interchange contain the seeds of the answer to your
final question, which, if I may paraphrase just a bit, is whether there's any hope of
reaching reasonable public-policy decisions when the details of the science germane to
those decisions are impenetrable to most citizens.
This is a hard problem.   Certainly the difficulty is not restricted to climate science
and policy, but applies also to nuclear-weapon science and policy,  nuclear-energy
science and policy, genetic science and policy, and much more.   But I don't think the
difficulties are insurmountable.   That's why I'm in the business I'm in, which is
teaching about and working on the intersection of science and technology with policy.
Most citizens cannot penetrate the details of what is known about the how the climate
works (and, of course, what is known even by the most knowledgeable climate scientists
about this is not everything one would like to know, and is subject to modification by
new data, new insights, new forms of analysis).  Neither would most citizens be able to
understand how a hydrogen bomb works (even if the details were not secret), or what
factors will determine the leak rates of radioactive nuclides from radioactive-waste
repositories, or what stem-cell research does and promises to be able to do.
But, as Amory Lovins once said in addressing the question of whether the public deserved
and could play a meaningful role in debates about nuclear-weapon policy, even though
most citizens would never understand the details of how nuclear weapons work or are
made, "You don't have to be a chicken to know what to do with an egg."   In other words,
for many (but not all) policy purposes, the details that are impenetrable do not matter.
There CAN be aspects of the details that do matter for public policy, of course.   In
those cases, it is the function and the responsibility of scientists who work across the
science-and-policy boundary to communicate the policy implications of these details in
ways that citizens and policy makers can understand.   And I believe it is the function
and responsibility of citizens and policy makers to develop, with the help of scientists
and technologists, a sufficient appreciation of how to reach judgments about
plausibility and credibility of communications about the science and technology relevant
to policy choices so that the citizens and policy makers are NOT disenfranchised in
policy decisions where science and technology are germane.
How this is best to be done is a more complicated subject than I am prepared to try to
explicate fully here.  (Alas, I have already spent more time on this interchange than I
could really afford from other current commitments.)   Suffice it to say, for now, that
improving the situation involves increasing at least somewhat, over time, the scientific
literacy of our citizens, including especially in relation to how science works, how to
distinguish an extravagant from a reasonable claim, how to think about probabilities of
who is wrong and who is right in a given scientific dispute (including the question of
burden of proof as you and I have been discussing it here), how consulting and polling
experts can illuminate issues even for those who don't understand everything that the
experts say, and why bodies like the National Academy of Sciences and the
Intergovernmental Panel on Climate Change deserve more credibility on the question of
where mainstream scientific opinion lies than the National Petroleum Council, the Sierra
Club, or the editorial page of the Wall Street Journal.
Regarding extravagant claims, you continue to argue that Mann et al. have been guilty of
this, but the formulation of theirs that you offer as evidence is not evidence of this
at all.  You quote them from the NYT in 1998, referring to a study Mann and co-authors
published in that year, as saying
"Our conclusion was that the warming of the past few decades appears to be closely
tied to emission of greenhouse gases by humans and not any of the natural factors."
and you ask "Does that seem to be careful in the nature of a claim?"   My answer is:
Yes, absolutely, their formulation is careful and appropriate.   Please note that they
did NOT say "Global warming is closely tied to emission of greenhouse gases by humans
and not any of the natural factors."   They said that THEIR CONCLUSION (from a
particular, specified study, published in NATURE) was that the warming of THE PAST FEW
DECADES (that is, a particular, specified part of the historical record) APPEARS (from
the evidence adduced in the specified study) to be closely tied...  This is a carefully
specified, multiply bounded statement, which accurately reflects what they looked at and
what they found.   And it is appropriately contingent --"APPEARS to be closely tied" --
allowing for the possibility that further analysis or new data could later lead to a
different perspective on what appears to be true.
With respect, it does not require a PhD in science to notice the appropriate boundedness
and contingency in the Mann et al. formulation.   It only requires an open mind, a
careful reading, and a degree of understanding of the character of scientific claims and
the wording appropriate to convey them that is accessible to any thoughtful citizen.
That is why I'm an optimist.
You go on to quote the respected scientist "Tom Quigley" as holding a contrary view to
that expressed by Mann.   But please note that:  (1) I don't know of any Tom Quigley
working in this field, so I suspect you mean to refer to the prominent climatologist Tom
Wigley;  (2) the statements you attribute to "Quiqley" do not directly contradict the
careful statement of Mann (that is, it is entirely consistent for Mann to say that his
study found that recent warming appears to be tied to human emissions and for Wigley to
say that that there are limits to how far one can go with this sort of analysis, without
either one being wrong);  and (3) Tom Wigley is one of the CO-AUTHORS of the resounding
Mann et al. refutation of Soon and Baliunas  (see attached PDF file).
I hope you have found my responses to be of some value.  I now must get on with other
things.
Best,
John Holdren
JOHN P. HOLDREN
-----------------------------------------------------------------------------
Teresa and John Heinz Professor of Environmental Policy
& Director, Program in Science, Technology, & Public Policy,
Belfer Center for Science and International Affairs,
John F. Kennedy School of Government
----------------------------------------------------------------------------
Professor of Environmental Science and Public Policy,
Department of Earth and Planetary Sciences
----------------------------------------------------------------------------
HARVARD UNIVERSITY
----------------------------------------------------------------------------
mail:  BCSIA, JFK School, 79 JFK St, Cambridge, MA 02138
phone: 617 495-1464 / fax 617 495-8963
email: john_holdren@harvard.edu
assistant:  Patricia_McLaughlin@ksg.harvard.edu, 617 495-1498
------------------------------------------------------------------------------
JOHN P. HOLDREN
-----------------------------------------------------------------------------
Teresa and John Heinz Professor of Environmental Policy
& Director, Program in Science, Technology, & Public Policy,
Belfer Center for Science and International Affairs,
John F. Kennedy School of Government
----------------------------------------------------------------------------
Professor of Environmental Science and Public Policy,
Department of Earth and Planetary Sciences
----------------------------------------------------------------------------
HARVARD UNIVERSITY
----------------------------------------------------------------------------
mail:  BCSIA, JFK School, 79 JFK St, Cambridge, MA 02138
phone: 617 495-1464 / fax 617 495-8963
email: john_holdren@harvard.edu
assistant:  Patricia_McLaughlin@ksg.harvard.edu, 617 495-1498
------------------------------------------------------------------------------
______________________________________________________________
Professor Michael E. Mann
Department of Environmental Sciences, Clark Hall
University of Virginia
Charlottesville, VA 22903
_______________________________________________________________________
e-mail: mann@virginia.edu   Phone: (434) 924-7770   FAX: (434) 982-2137
[4]
References
1.
2. mailto:john_holdren@harvard.edu
3. mailto:john_holdren@harvard.edu
4.


Dear Evelyn and Chris,
re. proposal review GC04-203, Meko et al. "A synthesis of 19th century climate data for the
United States from paleo, archival and instrumental sources".
I have read the "Reviewer conflict of interest and confidentiality..." document and can
state that I have no conflict of interest and will abide by the confidentiality provisions
etc.
I reviewed a very similar proposal by this group 1 year ago, and enclose my review of that
proposal below.  The new proposal has taken into account my two main concerns from last
time, which were:
(i) that creation only of a blended data set that contained a time varying mixture of proxy
and instrumental data would limit the usefulness because its quality would be time varying,
perhaps in an unquantified way, and independent study of errors between proxy and observed
data would be prevented; and
(ii) that the proposed work was not very innovative in terms of the applications for which
the new information would be used.
Both of these points have been addressed adequately and so I now rate it "Excellent (5)"
for scientific/technical merit, and "High (5)" for importance/relevance and applicability.
One issue that I would like to raise, however, is that the need for quantifying
uncertainty/error in the reconstructions/database is not given much coverage in the
proposal.  It is mentioned, but not focused on.  For many applications (testing models,
comparison with other reconstructions, detection of unusual climate trends/events),
explicitly quantified error estimates are essential.  These often change magnitude through
time, and thus should be estimated in such a way as to allow this.  They may also change
with time scale (often being lower for, e.g., a decadal mean than for a single year's
value), and again the error estimation method should capture this.  I do not think that
this issue detracts from the quality of the proposal.  Instead I am mentioning it in the
hope that this comment can be passed on to the proposers, in the event that the project is
funded, so that they can be prompted into placing the appropriate emphasis on quantifying
uncertainty.
Apologies for being late yet again, and best regards,
Tim
Date: Thu, 24 Oct 2002 17:14:31 +0000
Subject: confidential assessment of GC03-512
From: Tim Osborn
To:
CC:
,
Dear Irma and Chris,
Re. proposal review GC03-512, PI: David Meko "A 19th century data catalog"
First of all, I confirm that there is no conflict of interest etc.
Now to my review...
(1) Scientific Merit
Rating: Good
Comments:
I completely agree with the rationale behind improving data sets of 19th
century climate (see my comments below on "Relevance to climate change
programme"), and the proposers have identified the most relevant data
sources available for the US.  The objectives and workplan are generally
reasonable, but I have rated it "good" rather than "very good" or
"excellent" because it does not seem as scientifically innovative or
challenging as it might.  Some particular concerns are highlighted below.
I am very wary about the proposed approach of integrating the data sources
together to produce a single climate product.  Obviously the data sources
have to be used in combination, for calibration of proxy data or for
assessment of possibly dubious early instrumental data, *but* combining them
all into a single product only will be very restrictive for future use,
assessment, improvements.  Much better would be to produce intrumental-only
series for whatever length is available, and tree-ring only series for the
full length (i.e., into the late 19th and 20th centuries, despite the
availability of instrumental data for these periods).  Blending them into a
single analysis is of some, but limited, use and comparisons of different
periods and with (e.g.) model simulations can only ever be done by taking
into account error bars that vary dramatically in time and are only
estimates of the "true" errors - and the error estimates may be
underestimates if based only on residuals or covariances during the 20th
century.
No mention is made of using the 19th century data to consider key issues
such as difference between tree-ring and ground borehole temperatures (they
differ more in the 19th century, in terms of trend, than in other
centuries), possibly taking into account land-use change.  No mention is
made of using the 19th century data to assess multi-century temperature
reconstructions and why they differ.  These are issues of great importance.
No mention is investigating seasonal dependence of temperature changes,
which are greater in existing temperature products during the 19th century
than in the 20th century and which has important implications for the
calibration of proxy (including tree-ring) data against summer or annual
data and the need to more clearly define the true seasonal response of proxy
data.
Despite these concerns, the proposed work is certainly worthy of funding and
the extra items of interest that I mention above could be achieved using the
data generated here, in some future project.
(2) Relevance to climate change programme
Rating: High
Comments:
The 19th century is certainly of particular importance, not just for the
reasons outlined in the proposal but also because this century shows some of
the biggest disagreements in warming trend between various quasi-hemispheric
temperature reconstructions and between proxy and instrumental data and
between different seasons of instrumental data.  Additional data sources are
definitely required, and additional digitisation, homogenisation and
intercomparison of data sets is necessary.  For these reasons, work such as
that proposed here is essential for helping to refine answers to questions
such as how unusual is late twentieth century climate and detection of
climate change signals against the noise of natural climate variability.
Best regards
Tim


Dear All,
This has been passed along to me by someone whose identity will remain in confidence.
Who knows what trickery has been pulled or selective use of data  made. Its clear that
"Energy and Environment" is being run by the baddies--only a shill  for industry would have
republished the original Soon and Baliunas paper as submitted to "Climate Research" without
even editing it. Now apparently they're at it again...
My suggested response is:
1) to dismiss this as stunt, appearing in a so-called "journal" which is already known to
have defied standard practices of peer-review. It is clear, for example, that nobody we
know has been asked to "review" this so-called paper
2) to point out the claim is nonsense since the same basic result  has been obtained by
numerous other researchers, using different data, elementary compositing techniques, etc.
Who knows what sleight of hand the authors of this thing have pulled. Of course, the usual
suspects are going to try to peddle this crap. The important thing is to deny that this has
any intellectual credibility whatsoever and, if contacted by any media, to dismiss this for
the stunt that it is..
Thanks for your help,
mike
two people have a forthcoming 'Energy & Environment' paper that's being unveiled tomoro
(monday) that -- in the words of one Cato / Marshall/ CEI type -- "will claim that Mann
arbitrarily ignored paleo data within his own record and substituted other data for
missing values that dramatically affected his results.
When his exact analysis is rerun with all the data and with no data
substitutions, two very large warming spikes will appear that are greater than the 20th
century.
Personally, I'd offer that this was known by most people who understand Mann's
methodology:  it can be quite sensitive to the input data in the early centuries.
Anyway, there's going to be a lot of noise on this one, and knowing Mann's very thin
skin I am afraid he will react strongly, unless he has learned (as I hope he has) from
the past...."
______________________________________________________________
Professor Michael E. Mann
Department of Environmental Sciences, Clark Hall
University of Virginia
Charlottesville, VA 22903
_______________________________________________________________________
e-mail: mann@virginia.edu   Phone: (434) 924-7770   FAX: (434) 982-2137
[1]
References
1.


Dear Thomas, Fortunat,  Reto:
You might have wanted to check w/ us first, but thanks anyway for responding to this. We've
uncovered the error in what they did. They didn't use the proxy data available on our
public ftp site, which I had pointed them too--instead they used a spreadsheet file that my
associate Scott Rutherford had prepared. In this file, most of the early series were
overprinted at later years. This resulted in the reconstruction becoming increasingly
spurious as one goes further back in time--the estimates prior to 1700 or so were rendered
meaningless. There were also some other methodological errors that will be detailed
shortly, but this was the big one.
So they will probably have to retract the paper. You can find out more about this here, on
journalist David Appell's "blog":
[1]
We also have an op-ed piece going out this afternoon, further detailing the problems. Will
send that as soon as its available. I've attached a few other relevant documents, and I'm
forwarding another email I sent out to colleagues yesterday, just after I had discovered
the main problem in what they've done...
mike
______________________________________________________________
Professor Michael E. Mann
Department of Environmental Sciences, Clark Hall
University of Virginia
Charlottesville, VA 22903
_______________________________________________________________________
e-mail: mann@virginia.edu   Phone: (434) 924-7770   FAX: (434) 982-2137
[2]
Attachment Converted: "c:\eudora\attach\Journalists.re.EandEfin-revised.doc"
References
1.
2.


Guys, can you take a look at this.
I think that everything I say here is true! But we've got to be sure.
There are more technical things they did wrong that I want to add, but this is the critical
bit--what do you think. Comments? Thanks...
mike
________________________________________
The recent paper by McIntyre and McKitrick (Energy and Environment, 14, 751-771) claims to
be an "audit" of the analysis of Mann, Bradley and Hughes (1998) or "MBH98".  An audit
involves a careful examination, using the same data and following the exact procedures used
in the report or study being audited.  McIntyre and McKitrick ("MM") have done no such
thing, having used neither the data nor the procedures of MBH98. Their analysis is notable
only in how deeply they have misrepresented the data, methods, and results of MBH98.
Journals that receive critical comments on a previously published papers always provide the
authors who are being criticized an opportunity to review the study prior to publication,
and offer them the chance to respond.  This is standard operating procedure in any
legitimate peer-reviewed scientific journal. Mann and colleagues were never given this
opportunity, nor were any other leading paleoclimate scientists that we're familiar with.
It is unfortunate that the profound errors, and false and misleading statements, and
entirely spurious results provided in the  McIntyre and McKitrick article were ever allowed
to see the light of day by those would have been able to detect them. . We suspect the
extremely checkered history of "Energy and Environment" has some role to play in this. The
authors should retract their article immediately, and issue a public apology to the climate
research community for the injustice they have done in publishing and promoting this deeply
deceptive and flawed analysis.
Not only were critical errors made in their analysis that render it thoroughly invalid, but
there appear to have been several strikingly subjective decisions made to remove key
indicators of the original MBH98 network prior to AD 1600, with a dramatic impact on the
resulting reconstruction.  It is precisely the over which the numerous indicators were
removed (pre 1600 period) during which MM reconstruct anomalous warmth  that is in sharp
opposition to the cold conditions observed in MBH98 and  nearly  all other independent
published estimates that we know of.
While the authors dutifully cite the small inconsistency between the number of proxy
indicators reported by, and found in the public data archive, of Mann et al back in time
(there indeed appear to have been some minor typos in the MBH98 paper), it is odd that they
do not cite the number of indicators in their putative version of the Mann et al network
based on the independent collection of data, back time. The reader is literally left to do
a huge amount of detective work, based on the tables in their pages 20-23, to determine
just what data have been eliminated from the original Mann et al network. It seems odd,
indeed, that their "substitutions" of other versions (or in some case, only apparent, and
not actual, versions) of proxy data series for those in the original Mann et al (1998)
network has the selective effect of deleting key proxy indicators that contribute dramatic
cooling during the 16th century, when the MM reconstruction shows an anomalous warming
departure from the Mann et al (1998) and all other published Northern Hemisphere
temperature reconstructions.
Here are some blatant examples:
1) The authors (see their Figure 4) substitute a younger version of one of the Jacoby et al
Northern Treeline series for the older version used by MBH98. This substitution has effect
of removing a predictor of 15th century cooling [Incidentally, MM make much of the tendency
for some tree ring series, such as this one, to show an apparent cooling over the past
couple decades. Scientists with expertise in dendroclimatology know that this behavior
represents a  decrease in the sensitivity to temperature in recent decades that likely is
related to conditions other than temperature which are limiting tree growth]
2) The authors eliminate, without any justification, the entire dataset of 70 Western North
American (WNA) tree-ring series available between 1400 and 1600 (this dataset is
represented, by MBH98, in terms of a smaller number of representative Principal Component
time series). The leading pattern of variance in this data set exhibits conditions from
1400-1800 that are dramatically colder than the mid and late 20th  century, and a very
prominent cooling in the 15th century in particular. The authors eliminated this entire
dataset because they claimed that the underlying data was not available in the public
domain.
In point of fact, not only were the individual WNA data all available on the public ftp
site provided by Mann and colleagues:
[1]ftp://holocene.evsc.virginia.edu/pub/MBH98/TREE/ITRDB/NOAMER/, but they were also
available, despite the claims to the contrary by MM, on NOAA's website as well:
[2]ftp://ftp.ngdc.noaa.gov/paleo/treering/chronologies/northamerica/usa
The deletion of this critical (see Mann et al, 1999) dataset appears to  one of the more
important censorings performed by MM  that allows them to achieve their spurious result of
apparent 15th-16th century warmth.
We have not, as yet, finished determining just how many important indicators were subtly
censored from the MBH98 dataset by the various subjective substitutions described on pages
20-23. However, given the relatively small number of indicators available between 1400-1500
in the MBH98 network (22-24) and their elimination of some of the more critical ones, it
would appear that this subjective censoring of data, alone, explains the spurious,
misleading, and deceptive result achieved by the authors.
Incidentally, MBH98 go to great depths to perform careful cross-validation experiments as a
function of increasing sparseness of the candidate predictors back in time, to demonstrate
statistically significant reconstructive skill even for their earlier (1400-1450)
reconstruction interval. MM describe no cross-validation experiments. We wonder what the
verification resolved variance is for their reconstruction based on their 1400-1450
available network, during the independent latter 19th century period?
There are numerous other serious problems that would render the MM analysis completely
invalid, even in the absence of the serious issue raised above, and these are detailed
below
.
.
.
______________________________________________________________
Professor Michael E. Mann
Department of Environmental Sciences, Clark Hall
University of Virginia
Charlottesville, VA 22903
_______________________________________________________________________
e-mail: mann@virginia.edu   Phone: (434) 924-7770   FAX: (434) 982-2137
[3]
References
1. ftp://holocene.evsc.virginia.edu/pub/MBH98/TREE/ITRDB/NOAMER/
2. ftp://ftp.ngdc.noaa.gov/paleo/treering/chronologies/northamerica/usa
3.


Tim, Phil, Keef:
I suggest a way out of this mess.  Because of the complexity of the
arguments involved, to an uniformed observer it all might be viewed as just
scientific nit-picking by "for" and "against" global warming
proponents.  However, if an "independent group" such as you guys at CRU
could make a statement as to whether the M&M effort is truly an "audit",
and if they did it right, I think that would go a long way to defusing the
issue.
It's clear from the figure that Reno Knuti sent yesterday that something
pretty whacky happened in their analysis prior to ~AD1600, and this led
Mike to figure out the problem.  See:
file:///c:/eudora/attach/nh_temp_rec.jpg
If you are willing, a quick and forceful statement from The Distinguished
CRU Boys would help quash further arguments, although here, at least, it is
already quite out of control.....yesterday in the US Senate the debate
opened on the McCain-Lieberman bill to control CO2 emissions from power
plants.  Sen Inhofe stood up & showed the M & M figure and stated that Mann
et al--& the IPCC assessment --was now disproven and so there was no reason
to control CO2 emissions.....I wonder how many times a "scientific" paper
gets reported on in the Senate 3 days after it is published....
Ray


Hi Keith,
sorry--yes, I think the Nature idea would be great. Definitely give it a try!
thanks,
mike
At 06:53 PM 10/30/2003 +0000, Keith Briffa wrote:
Things obviously moving over there - this result looks good.Just thought I'd send this
first bit (up to dotted line) of edited version ,  to illustrate possible toning down?
Have to go now and feed daughter . Will wait til see your joint version first thing
tomorrow - rest assured, that am entirely with you on this and still appalled by the MM
stuff - but keeping your distance and calm stance is still urged.
all the best to all
any objections if I talk to Nature tomorrow?
Keith
At 01:31 PM 10/30/03 -0500, Michael E. Mann wrote:
Guys,
So the verification RE for the "censored" NH mean reconstruction?  -6.64
The verification RE for the original MBH98 NH mean reconstruction: 0.42
I think the case is really strong now!
What if were to eliminate the discussion of all the other technical details (and just
say they exist), and state more nicely that these series were effectively censored by
their substitutions, and that by removing those series which they censored, I get a
similar result, with a dismal RE.
And most people would keep the RE of 0.42 over the RE of -6, right? So this would make
that point. I think we also need to say something about the process, etc. (the intro was
based on something that Malcolm/Ray had originally crafted).
Thoughts, comments? Thanks,
mike
I'm thinking of a note saying basically this, and attaching this figure.
Could everybody sign on to something like this?
Thanks for all your help,
mike
At 05:11 PM 10/30/2003 +0000, Keith Briffa wrote:
Ray et al
I agree with this idea in principle . Whatever scientific differences and fascination
with the nuances of techniques we may /may not share, this whole process represents the
most despicable example of slander and down right deliberate perversion of the
scientific process , and bias (unverified) work being used to influence public
perception and due political process. It is , however, essential that you (we) do not
get caught up in the frenzy that these people are trying to generate, and that will more
than likely lead to error on our part or some premature remarks that we might regret. I
do think the statement re Mike's results needs making , but only after it can be based
on repeated work and in full collaboration of us all. I am happy to push Tim to take the
lead and collaborate in this - and I feel we could get sanction very quickly from the
DEFRA if needed. BUT this must be done calmly , and in the meantime a restrained
statement but out saying we have full confidence in Mike's objectivity and independence
- which we can not say of the sceptics. In fact I am moved tomorrow to contact Nature
and urge them to do an editorial on this . The political machinations in Washington
should NOT dictate the agenda or scheduling of the work - but some cool statement can be
made saying we believe the "prats have really fucked up someway" - and that the
premature publication of their paper is reprehensible . Much of the detail in Mikes
response though is not sensible (sorry Mike) and is rising to their bate.
Keith
At 11:55 AM 10/30/03 -0500, raymond s. bradley wrote:
Tim, Phil, Keef:
I suggest a way out of this mess.  Because of the complexity of the arguments involved,
to an uniformed observer it all might be viewed as just scientific nit-picking by "for"
and "against" global warming proponents.  However, if an "independent group" such as you
guys at CRU could make a statement as to whether the M&M effort is truly an "audit", and
if they did it right, I think that would go a long way to defusing the issue.
It's clear from the figure that Reno Knuti sent yesterday that something pretty whacky
happened in their analysis prior to ~AD1600, and this led Mike to figure out the
problem.  See:
[1]file:///c:/eudora/attach/nh_temp_rec.jpg
If you are willing, a quick and forceful statement from The Distinguished CRU Boys would
help quash further arguments, although here, at least, it is already quite out of
control.....yesterday in the US Senate the debate opened on the McCain-Lieberman bill to
control CO2 emissions from power plants.  Sen Inhofe stood up & showed the M & M figure
and stated that Mann et al--& the IPCC assessment --was now disproven and so there was
no reason to control CO2 emissions.....I wonder how many times a "scientific" paper gets
reported on in the Senate 3 days after it is published....
Ray
--
Professor Keith Briffa,
Climatic Research Unit
University of East Anglia
Norwich, NR4 7TJ, U.K.
Phone: +44-1603-593909
Fax: +44-1603-507784
[2]
______________________________________________________________
Professor Michael E. Mann
Department of Environmental Sciences, Clark Hall
University of Virginia
Charlottesville, VA 22903
_______________________________________________________________________
e-mail: mann@virginia.edu   Phone: (434) 924-7770   FAX: (434) 982-2137
[3]
--
Professor Keith Briffa,
Climatic Research Unit
University of East Anglia
Norwich, NR4 7TJ, U.K.
Phone: +44-1603-593909
Fax: +44-1603-507784
[4]
______________________________________________________________
Professor Michael E. Mann
Department of Environmental Sciences, Clark Hall
University of Virginia
Charlottesville, VA 22903
_______________________________________________________________________
e-mail: mann@virginia.edu   Phone: (434) 924-7770   FAX: (434) 982-2137
[5]
References
1. file://c:\eudora\attach\nh_temp_rec.jpg/
2.
3.
4.
5.