Climategate 3.0 has occurred - the password has been released

Anthony Watts
WattsUpWithThat.com
Wed, 13 Mar 2013 12:12 UTC

A number of climate skeptic bloggers (myself included) have received this message yesterday. While I had planned to defer announcing this until a reasonable scan could be completed, some other bloggers have let the cat out of the bag. I provide this introductory email sent by "FOIA" without editing or comment. I do have one email, which I found quite humorous, which I will add at the end so that our friends know that this is valid. Update - the first email I posted apparently was part of an earlier release (though I had not seen it, there are a number of duplicates in the all.zip file) so I have added a second one.- Anthony

===========================================================
Subject: FOIA 2013: the password

It's time to tie up loose ends and dispel some of the speculation surrounding the Climategate affair.

Indeed, it's singular "I" this time. After certain career developments I can no longer use the papal plural ;-)

If this email seems slightly disjointed it's probably my linguistic background and the problem of trying to address both the wider audience (I expect this will be partially reproduced sooner or later) and the email recipients (whom I haven't decided yet on).

The "all.7z" password is [redacted]

DO NOT PUBLISH THE PASSWORD. Quote other parts if you like.

Releasing the encrypted archive was a mere practicality. I didn't want to keep the emails lying around.

I prepared CG1 & 2 alone. Even skimming through all 220.000 emails would have taken several more months of work in an increasingly unfavorable environment.

Dumping them all into the public domain would be the last resort. Majority of the emails are irrelevant, some of them probably sensitive and socially damaging.

To get the remaining scientifically (or otherwise) relevant emails out, I ask you to pass this on to any motivated and responsible individuals who could volunteer some time to sift through the material for eventual release.

Filteringredacting personally sensitive emails doesn't require special expertise.

I'm not entirely comfortable sending the password around unsolicited, but haven't got better ideas at the moment. If you feel this makes you seemingly "complicit" in a way you don't like, don't take action.

I don't expect these remaining emails to hold big surprises. Yet it's possible that the most important pieces are among them. Nobody on the planet has held the archive in plaintext since CG2.

That's right; no conspiracy, no paid hackers, no Big Oil. The Republicans didn't plot this. USA politics is alien to me, neither am I from the UK. There is life outside the Anglo-American sphere.

If someone is still wondering why anyone would take these risks, or sees only a breach of privacy here, a few words...

The first glimpses I got behind the scenes did little to garner my trust in the state of climate science - on the contrary. I found myself in front of a choice that just might have a global impact.

Briefly put, when I had to balance the interests of my own safety, privacycareer of a few scientists, and the well-being of billions of people living in the coming several decades, the first two weren't the decisive concern.

It was me or nobody, now or never. Combination of several rather improbable prerequisites just wouldn't occur again for anyone else in the foreseeable future. The circus was about to arrive in Copenhagen. Later on it could be too late.

Most would agree that climate science has already directed where humanity puts its capability, innovation, mental and material "might". The scale will grow ever grander in the coming decades if things go according to script. We're dealing with $trillions and potentially drastic influence on practically everyone.

Wealth of the surrounding society tends to draw the major brushstrokes of a newborn's future life. It makes a huge difference whether humanity uses its assets to achieve progress, or whether it strives to stop and reverse it, essentially sacrificing the less fortunate to the climate gods.

We can't pour trillions in this massive hole-digging-and-filling-up endeavor and pretend it's not away from something and someone else.

If the economy of a region, a country, a city, etc. deteriorates, what happens among the poorest? Does that usually improve their prospects? No, they will take the hardest hit. No amount of magical climate thinking can turn this one upside-down.

It's easy for many of us in the western world to accept a tiny green inconvenience and then wallow in that righteous feeling, surrounded by our "clean" technology and energy that is only slightly more expensive if adequately subsidized.

Those millions and billions already struggling with malnutrition, sickness, violence, illiteracy, etc. don't have that luxury. The price of "climate protection" with its cumulative and collateral effects is bound to destroy and debilitate in great numbers, for decades and generations.

Conversely, a "game-changer" could have a beneficial effect encompassing a similar scope.

If I had a chance to accomplish even a fraction of that, I'd have to try. I couldn't morally afford inaction. Even if I risked everything, would never get personal compensation, and could probably never talk about it with anyone.

I took what I deemed the most defensible course of action, and would do it again (although with slight alterations - trying to publish something truthful on RealClimate was clearly too grandiose of a plan ;-).

Even if I have it all wrong and these scientists had some good reason to mislead us (instead of making a strong case with real data) I think disseminating the truth is still the safest bet by far.

Big thanks to Steve and Anthony and many others. My contribution would never have happened without your work (whether or not you agree with the views stated).

Oh, one more thing. I was surprised to learn from a "progressive" blog, corroborated by a renowned "scientist", that the releases were part of a coordinated campaign receiving vast amounts of secret funding from shady energy industry groups.

I wasn't aware of the arrangement but warmly welcome their decision to support my project. For that end I opened a bitcoin address: 1HHQ36qbsgGZWLPmiUjYHxQUPJ6EQXVJFS.

More seriously speaking, I accept, with gratitude, modest donations to support The (other) Cause. The address can also serve as a digital signature to ward off those identity thefts which are part of climate scientists' repertoire of tricks these days.

Keep on the good work. I won't be able to use this email address for long so if you reply, I can't guarantee reading or answering. I will several batches, to anyone I can think of.

Over and out.

Mr. FOIA
===============================================================

Here is one email that I found interesting and humorous, email addresses redacted as a courtesy. Note the bolding:

===============================================================

- - Original Message - -
From: Simon Tett
Sent: Saturday, August 25, 2001 1:36 PM
To: [e-mail]
Cc: [e-mail] ; [e-mail]
Subject: Paleo-Paper

Mat,
The papers looks very good. Hope these comments aren't too late.... I
don't think I need to see it again.

Simon

Response to reviewers

I couldn't read your letter - PS files as attachments seem to get
munged by our firewall/email scanner so I've just looked at the paper
to see if I think you've dealt with the reviewers comments.

Editors comments:

3) Don't think you have dealt with the enhanced multi-decadal
variability in the paper.

Reviewer B.

1) Didn't see a justification for use of tree-rings and not using ice
cores - the obvious one is that ice cores are no good - see Jones et
al, 1998.

2) No justification for regional reconstructions rather than what Mann
et al did (I don't think we can say we didn't do Mann et al because
we think it is crap!)

3) No justification in the paper for the 9 regions. I think there is
justification in the JGR Briffa paper.

4) That is a good point - I would strongly suspect that the control has
a lot less variance than the observations over the last century -
not the ALL run though!

5) No response to this in the paper. I suspect we are doing better
stats than all the rest though!

Specific Questions/comments

1) That is a good point: How about (though a bit germanic)
"Comparison of simulated northern hemisphere variability with
paleo-temperature ..."

Didn't see that you had dealt with points 5 and 6.

Ditto for point 11.

Figures.

2-4 seem to be much as submitted!

Figs 5-8 - do you want to use colour? It would cost!

Ref C.

Don't seem to have dealt with point a) and it is quite an important
point as well!

Point b is a reasonable point which I think you go some way to dealing
with. I suggest you stress on page 20 the "exploratory" nature of our
analysis. I am just about to start such a run once I have sorted out
the orbital forcings and how to calculate their radiative forcings.

Point c - not sure what the referee is saying here!

Comments on the MS.

Page 9 "pith" means
Same sentence I think you need to add that they are grouped by
species as well (the rest of the para implies that is what is
done).

Last sentence of penultimate para: stress that decadal to century
scale variability is what we are interested mainly because of its
importance in deciding if recent climate change is anthropogenic or
natural.

First full para on page 13 - didn't really follow this para.

2nd para, line 11 consider "in comparison" -> "when compared"

Page 14, first para - consider expanding the abbreviations i.e CAS ->
CAS (Central Asia).

Page 20, last para. insert 'in the four simulations' after 'six
"negative spikes"'.

Section 10 should be Appendix A.

-
Dr Simon Tett Managing Scientist, Data development and applications.
Met Office Hadley Centre Climate Prediction and Research
London Road Bracknell Berkshire RG12 2SY United Kingdom
Tel: +44 xxxxxxx Fax: +44 xxxxxx
E-mail: xxxxxxx

====================================================

Second email (added after original post)

====================================================

- - Original Message - -
From: Michael E. Mann
Sent: Wednesday, May 02, 2001 8:14 AM
To: Edward Cook
Cc: tom crowley ; Michael E. Mann ; esper@xxxxxx ; Jonathan
Overpeck ; Keith Briffa ; mhughes@xxxxxxx ; rbradley@xxxxxx
Subject: Re: hockey stick

<x-flowed>
Hi Ed,

Thanks for your message. I'm forwarding this to Ray and Malcolm to reply to
some of your statements below,

mike

At 10:59 AM 5/2/01 -0400, Edward Cook wrote:
> >Ed,
> >
> >heard some rumor that you are involved in a non-hockey stick
> >reconstruction
> >of northern hemisphere temperatures. I am very intrigued to learn about
> >this - are these results suggesting the so called Medieval Warm Period
> >may
> >be warmer than the early/mid 20th century?
> >
> >any enlightenment on this would be most appreciated, Tom
> >
> >
> >
> >Thomas J. Crowley
> >Dept. of Oceanography
> >Texas A&M University
> >College Station, TX 77843-3146
> >979-xxxxxxx
> >979-xxxxxxx
> >979-xxxxxxx
>
>Hi Tom,
>
>As rumors often are, the one you heard is not entirely accurate. So, I will
>take some time here to explain for you, Mike, and others exactly what was
>done and what the motivation was, in an effort to hopefully avoid any
>misunderstanding. I especially want to avoid any suggestion that this work
>was being done to specifically counter or refute the "hockey stick".
>However, it does suggest (as do other results from your EBM, Peck's work,
>the borehole data, and Briffa and Jones large-scale proxy estimates) that
>there are unresolved (I think) inconsistencies in the low-frequency aspects
>of the hockey stick series compared to other results. So, any comparisons
>with the hockey stick were made with that spirit in mind.
>
>What Jan Esper and I are working on (mostly Jan with me as second author)
>is a paper that was in response to Broecker's Science Perspectives piece on
>the Medieval Warm Period. Specifically, we took strong exception to his
>claim that tree rings are incapable of preserving century time scale
>temperature variability. Of course, if Broecker had read the literature, he
>would have known that what he claimed was inaccurate. Be that as it may,
>Jan had been working on a project, as part of his post-doc here, to look at
>large-scale, low-frequency patterns of tree growth and climate in long
>tree-ring records provided to him by Fritz Schweingruber. With the addition
>of a couple of sites from foxtail pine in California, Jan amassed a
>collection of 14 tree-ring sites scattered somewhat uniformly over the
>30-70 degree NH latitude band, with most extending back 1000-1200 years.
>All of the sites are from temperature-sensitive locations (i.e. high
>elevation or high northern latitude. It is, as far as I know, the largest,
>longest, and most spatially representative set of such
>temperature-sensitive tree-ring data yet put together for the NH
>extra-tropics.
>
>In order to preserve maximum low-frequency variance, Jan used the Regional
>Curve Standardization (RCS) method, used previously by Briffa and myself
>with great success. Only here, Jan chose to do things in a somewhat radical
>fashion. Since the replication at each site was generally insufficient to
>produce a robust RCS chronology back to, say, AD 1000, Jan pooled all of
>the original measurement series into 2 classes of growth trends: non-linear
>(~700 ring-width series) and linear (~500 ring-width series). He than
>performed independent RCS on the each of the pooled sets and produced 2 RCS
>chronologies with remarkably similar multi-decadal and centennial
>low-frequency characteristics. These chronologies are not good at
>preserving high-frquency climate information because of the scattering of
>sites and the mix of different species, but the low-frequency patterns are
>probably reflecting the same long-term changes in temperature. Jan than
>averaged the 2 RCS chronologies together to produce a single chronology
>extending back to AD 800. It has a very well defined Medieval Warm Period -
>Little Ice Age - 20th Century Warming pattern, punctuated by strong decadal
>fluctuations of inferred cold that correspond well with known histories of
>neo-glacial advance in some parts of the NH. The punctuations also appear,
>in some cases, to be related to known major volcanic eruptions.
>
>Jan originally only wanted to show this NH extra-tropical RCS chronology in
>a form scaled to millimeters of growth to show how forest productivity and
>carbon sequestration may be modified by climate variability and change over
>relatively long time scales. However, I encouraged him to compare his
>series with NH instrumental temperature data and the proxy estimates
>produced by Jones, Briffa, and Mann in order bolster the claim that his
>unorthodox method of pooling the tree-ring data was producing a record that
>was indeed related to temperatures in some sense. This he did by linearly
>rescaling his RCS chronology from mm of growth to temperature anomalies. In
>so doing, Jan demonstrated that his series, on inter-decadal time scales
>only, was well correlated to the annual NH instrumental record. This result
>agreed extremely well with those of Jones and Briffa. Of course, some of
>the same data were used by them, but probably not more than 40 percent
>(Briffa in particular), so the comparison is based on mostly, but not
>fully, independent data. The similarity indicated that Jan's approach was
>valid for producing a useful reconstruction of multi-decadal temperature
>variability (probably weighted towards the warm-season months, but it is
>impossible to know by how much) over a larger region of the NH
>extra-tropics than that produced before by Jones and Briffa. It also
>revealed somewhat more intense cooling in the Little Ice Age that is more
>consistent with what the borehole temperatures indicate back to AD 1600.
>This result also bolsters the argument for a reasonably large-scale
>Medieval Warm Period that may not be as warm as the late 20th century, but
>is of much(?) greater significance than that produced previously.
>
>Of course, Jan also had to compare his record with the hockey stick since
>that is the most prominent and oft-cited record of NH temperatures covering
>the past 1000 years. The results were consistent with the differences shown
>by others, mainly in the century-scale of variability. Again, the Esper
>series shows a very strong, even canonical, Medieval Warm Period - Little
>Ice Age - 20th Century Warming pattern, which is largely missing from the
>hockey stick. Yet the two series agree reasonably well on inter-decadal
>timescales, even though they may not be 1:1 expressions of the same
>temperature window (i.e. annual vs. warm-season weighted). However, the
>tree-ring series used in the hockey stick are warm-season weighted as well,
>so the difference between "annual" and "warm-season weighted" is probably
>not as large as it might seem, especially before the period of instrumental
>data (e.g. pre-1700) in the hockey stick. So, they both share a significant
>degree of common interdecal temperature information (and some, but not
>much, data), but do not co-vary well on century timescales. Again, this has
>all been shown before by others using different temperature
>reconstructions, but Jan's result is probably the most comprehensive
>expression (I believe) of extra-tropical NH temperatures back to AD 800 on
>multi-decadal and century time scales.
>
>Now back to the Broecker perspectives piece. I felt compelled to refute
>Broecker's erroneous claim that tree rings could not preserve long-term
>temperature information. So, I organized a "Special Wally Seminar" in which
>I introduced the topic to him and the packed audience using Samuel
>Johnson's famous "I refute it thus" statement in the form of "Jan Esper and
>I refute Broecker thus". Jan than presented, in a very detailed and well
>espressed fashion, his story and Broecker became an instant convert. In
>other words, Wally now believes that long tree-ring records, when properly
>selected and processed, can preserve low-frequency temperature variability
>on centennial time scales. Others in the audience came away with the same
>understanding, one that we dendrochronologists always knew to be the case.
>This was the entire purpose of Jan's work and the presentation of it to
>Wally and others. Wally had expressed some doubts about the hockey stick
>previously to me and did so again in his perspectives article. So, Jan's
>presentation strongly re-enforced Wally's opinion about the hockey stick,
>which he has expressed to others including several who attended a
>subsequent NOAA meeting at Lamont. I have no control over what Wally says
>and only hope that we can work together to reconcile, in a professional,
>friendly manner, the differences between the hockey stick and other proxy
>temperature records covering the past 1000 years. This I would like to do.
>
>I do think that the Medieval Warm Period was a far more significant event
>than has been recognized previously, as much because the high-resolution
>data to evaluate it had not been available before. That is much less so the
>case now. It is even showing up strongly now in long SH tree-ring series.
>However, there is still the question of how strong this event was in the
>tropics. I maintain that we do not have the proxies to tell us that now.
>The tropical ice core data are very difficult to interpret as temperature
>proxies (far worse than tree rings for sure and maybe even unrelated to
>temperatures in any simple linear sense as is often assumed), so I do not
>believe that they can be used alone as records to test for the existence of
>a Medieval Warm Period in the tropics. That being the case, there are
>really no other high-resolution records from the tropics to use, and the
>teleconnections between long extra-tropical proxies and the tropics are, I
>believe, far too tenuous and probably unstable to use to sort out this
>issue.
>
>So, at this stage I would argue that the Medieval Warm Period was probably
>a global extra-tropical event, at the very least, with warmth that was
>persistent and probably comparable to much of what we have experienced in
>the 20th century. However, I would not claim (and nor would Jan) that it
>exceeded the warmth of the late 20th century. We simply do not have the
>precision or the proxy replication to say that yet. This being said, I do
>find the dismissal of the Medieval Warm Period as a meaningful global event
>to be grossly premature and probably wrong. Kind of like Mark Twain's
>commment that accounts of his death were greatly exaggerated. If, as some
>people believe, a degree of symmetry in climate exists between the
>hemispheres, which would appear to arise from the tropics, then the
>existence of a Medieval Warm Period in the extra-tropics of the NH and SH
>argues for its existence in the tropics as well. Only time and an enlarged
>suite of proxies that extend into the tropics will tell if this is true.
>
>I hope that what I have written clarifies the rumor and expresses my views
>more completely and accurately.
>
>Cheers,
>
>Ed
>
>==================================
>Dr. Edward R. Cook
>Doherty Senior Scholar
>Tree-Ring Laboratory
>Lamont-Doherty Earth Observatory
>Palisades, New York 10964 USA
>Phone: [phone]
>Fax: [phone]
>Email: drdendro@xxxxxxx
>==================================

_______________________________________________________________________
Professor Michael E. Mann
Department of Environmental Sciences, Clark Hall
University of Virginia
Charlottesville, VA 22903
_______________________________________________________________________
e-mail: mann@xxxxxxx Phone: [phone] FAX: [phone]

http://www.evsc.virginia.edu/faculty/people/mann.shtml

- - Original Message - -
From: Michael E. Mann
Sent: Wednesday, May 02, 2001 8:14 AM
To: Edward Cook
Cc: tom crowley ; Michael E. Mann ; [e-mail] ; Jonathan
Overpeck ; Keith Briffa ; [e-mail] ; [e-mail]
Subject: Re: hockey stick

<x-flowed>
Hi Ed,

Thanks for your message. I'm forwarding this to Ray and Malcolm to reply to
some of your statements below,

mike

At 10:59 AM 5/2/01 -0400, Edward Cook wrote:
> >Ed,
> >
> >heard some rumor that you are involved in a non-hockey stick
> >reconstruction
> >of northern hemisphere temperatures. I am very intrigued to learn about
> >this - are these results suggesting the so called Medieval Warm Period
> >may
> >be warmer than the early/mid 20th century?
> >
> >any enlightenment on this would be most appreciated, Tom
> >
> >
> >
> >Thomas J. Crowley
> >Dept. of Oceanography
> >Texas A&M University
> >College Station, TX 77843-3146
> >979-845-0795
> >979-847-8879 (fax)
> >979-845-6331 (alternate fax)
>
>Hi Tom,
>
>As rumors often are, the one you heard is not entirely accurate. So, I will
>take some time here to explain for you, Mike, and others exactly what was
>done and what the motivation was, in an effort to hopefully avoid any
>misunderstanding. I especially want to avoid any suggestion that this work
>was being done to specifically counter or refute the "hockey stick".
>However, it does suggest (as do other results from your EBM, Peck's work,
>the borehole data, and Briffa and Jones large-scale proxy estimates) that
>there are unresolved (I think) inconsistencies in the low-frequency aspects
>of the hockey stick series compared to other results. So, any comparisons
>with the hockey stick were made with that spirit in mind.
>
>What Jan Esper and I are working on (mostly Jan with me as second author)
>is a paper that was in response to Broecker's Science Perspectives piece on
>the Medieval Warm Period. Specifically, we took strong exception to his
>claim that tree rings are incapable of preserving century time scale
>temperature variability. Of course, if Broecker had read the literature, he
>would have known that what he claimed was inaccurate. Be that as it may,
>Jan had been working on a project, as part of his post-doc here, to look at
>large-scale, low-frequency patterns of tree growth and climate in long
>tree-ring records provided to him by Fritz Schweingruber. With the addition
>of a couple of sites from foxtail pine in California, Jan amassed a
>collection of 14 tree-ring sites scattered somewhat uniformly over the
>30-70 degree NH latitude band, with most extending back 1000-1200 years.
>All of the sites are from temperature-sensitive locations (i.e. high
>elevation or high northern latitude. It is, as far as I know, the largest,
>longest, and most spatially representative set of such
>temperature-sensitive tree-ring data yet put together for the NH
>extra-tropics.
>
>In order to preserve maximum low-frequency variance, Jan used the Regional
>Curve Standardization (RCS) method, used previously by Briffa and myself
>with great success. Only here, Jan chose to do things in a somewhat radical
>fashion. Since the replication at each site was generally insufficient to
>produce a robust RCS chronology back to, say, AD 1000, Jan pooled all of
>the original measurement series into 2 classes of growth trends: non-linear
>(~700 ring-width series) and linear (~500 ring-width series). He than
>performed independent RCS on the each of the pooled sets and produced 2 RCS
>chronologies with remarkably similar multi-decadal and centennial
>low-frequency characteristics. These chronologies are not good at
>preserving high-frquency climate information because of the scattering of
>sites and the mix of different species, but the low-frequency patterns are
>probably reflecting the same long-term changes in temperature. Jan than
>averaged the 2 RCS chronologies together to produce a single chronology
>extending back to AD 800. It has a very well defined Medieval Warm Period -
>Little Ice Age - 20th Century Warming pattern, punctuated by strong decadal
>fluctuations of inferred cold that correspond well with known histories of
>neo-glacial advance in some parts of the NH. The punctuations also appear,
>in some cases, to be related to known major volcanic eruptions.
>
>Jan originally only wanted to show this NH extra-tropical RCS chronology in
>a form scaled to millimeters of growth to show how forest productivity and
>carbon sequestration may be modified by climate variability and change over
>relatively long time scales. However, I encouraged him to compare his
>series with NH instrumental temperature data and the proxy estimates
>produced by Jones, Briffa, and Mann in order bolster the claim that his
>unorthodox method of pooling the tree-ring data was producing a record that
>was indeed related to temperatures in some sense. This he did by linearly
>rescaling his RCS chronology from mm of growth to temperature anomalies. In
>so doing, Jan demonstrated that his series, on inter-decadal time scales
>only, was well correlated to the annual NH instrumental record. This result
>agreed extremely well with those of Jones and Briffa. Of course, some of
>the same data were used by them, but probably not more than 40 percent
>(Briffa in particular), so the comparison is based on mostly, but not
>fully, independent data. The similarity indicated that Jan's approach was
>valid for producing a useful reconstruction of multi-decadal temperature
>variability (probably weighted towards the warm-season months, but it is
>impossible to know by how much) over a larger region of the NH
>extra-tropics than that produced before by Jones and Briffa. It also
>revealed somewhat more intense cooling in the Little Ice Age that is more
>consistent with what the borehole temperatures indicate back to AD 1600.
>This result also bolsters the argument for a reasonably large-scale
>Medieval Warm Period that may not be as warm as the late 20th century, but
>is of much(?) greater significance than that produced previously.
>
>Of course, Jan also had to compare his record with the hockey stick since
>that is the most prominent and oft-cited record of NH temperatures covering
>the past 1000 years. The results were consistent with the differences shown
>by others, mainly in the century-scale of variability. Again, the Esper
>series shows a very strong, even canonical, Medieval Warm Period - Little
>Ice Age - 20th Century Warming pattern, which is largely missing from the
>hockey stick. Yet the two series agree reasonably well on inter-decadal
>timescales, even though they may not be 1:1 expressions of the same
>temperature window (i.e. annual vs. warm-season weighted). However, the
>tree-ring series used in the hockey stick are warm-season weighted as well,
>so the difference between "annual" and "warm-season weighted" is probably
>not as large as it might seem, especially before the period of instrumental
>data (e.g. pre-1700) in the hockey stick. So, they both share a significant
>degree of common interdecal temperature information (and some, but not
>much, data), but do not co-vary well on century timescales. Again, this has
>all been shown before by others using different temperature
>reconstructions, but Jan's result is probably the most comprehensive
>expression (I believe) of extra-tropical NH temperatures back to AD 800 on
>multi-decadal and century time scales.
>
>Now back to the Broecker perspectives piece. I felt compelled to refute
>Broecker's erroneous claim that tree rings could not preserve long-term
>temperature information. So, I organized a "Special Wally Seminar" in which
>I introduced the topic to him and the packed audience using Samuel
>Johnson's famous "I refute it thus" statement in the form of "Jan Esper and
>I refute Broecker thus". Jan than presented, in a very detailed and well
>espressed fashion, his story and Broecker became an instant convert. In
>other words, Wally now believes that long tree-ring records, when properly
>selected and processed, can preserve low-frequency temperature variability
>on centennial time scales. Others in the audience came away with the same
>understanding, one that we dendrochronologists always knew to be the case.
>This was the entire purpose of Jan's work and the presentation of it to
>Wally and others. Wally had expressed some doubts about the hockey stick
>previously to me and did so again in his perspectives article. So, Jan's
>presentation strongly re-enforced Wally's opinion about the hockey stick,
>which he has expressed to others including several who attended a
>subsequent NOAA meeting at Lamont. I have no control over what Wally says
>and only hope that we can work together to reconcile, in a professional,
>friendly manner, the differences between the hockey stick and other proxy
>temperature records covering the past 1000 years. This I would like to do.
>
>I do think that the Medieval Warm Period was a far more significant event
>than has been recognized previously, as much because the high-resolution
>data to evaluate it had not been available before. That is much less so the
>case now. It is even showing up strongly now in long SH tree-ring series.
>However, there is still the question of how strong this event was in the
>tropics. I maintain that we do not have the proxies to tell us that now.
>The tropical ice core data are very difficult to interpret as temperature
>proxies (far worse than tree rings for sure and maybe even unrelated to
>temperatures in any simple linear sense as is often assumed), so I do not
>believe that they can be used alone as records to test for the existence of
>a Medieval Warm Period in the tropics. That being the case, there are
>really no other high-resolution records from the tropics to use, and the
>teleconnections between long extra-tropical proxies and the tropics are, I
>believe, far too tenuous and probably unstable to use to sort out this
>issue.
>
>So, at this stage I would argue that the Medieval Warm Period was probably
>a global extra-tropical event, at the very least, with warmth that was
>persistent and probably comparable to much of what we have experienced in
>the 20th century. However, I would not claim (and nor would Jan) that it
>exceeded the warmth of the late 20th century. We simply do not have the
>precision or the proxy replication to say that yet. This being said, I do
>find the dismissal of the Medieval Warm Period as a meaningful global event
>to be grossly premature and probably wrong. Kind of like Mark Twain's
>commment that accounts of his death were greatly exaggerated. If, as some
>people believe, a degree of symmetry in climate exists between the
>hemispheres, which would appear to arise from the tropics, then the
>existence of a Medieval Warm Period in the extra-tropics of the NH and SH
>argues for its existence in the tropics as well. Only time and an enlarged
>suite of proxies that extend into the tropics will tell if this is true.
>
>I hope that what I have written clarifies the rumor and expresses my views
>more completely and accurately.
>
>Cheers,
>
>Ed
>
>==================================
>Dr. Edward R. Cook
>Doherty Senior Scholar
>Tree-Ring Laboratory
>Lamont-Doherty Earth Observatory
>Palisades, New York 10964 USA
>Phone: [phone]
>Fax: [phone]
>Email: [e-mail]
>==================================

_______________________________________________________________________
Professor Michael E. Mann
Department of Environmental Sciences, Clark Hall
University of Virginia
Charlottesville, VA 22903
_______________________________________________________________________
e-mail: [e-mail] Phone: [phone] FAX: [phone]
http://www.evsc.virginia.edu/faculty/people/mann.shtml