Climategate email revisited: Ed Cook throws the tree ring circus under the bus

Posted: May 16, 2017 by tallbloke in Accountability, alarmism, climate, Dataset, History, IPCC

Just a little reminder of the science still championed by Al Gore, Barack Obama, the UN IPCC, the UK parliament’s climate change committee and all those august institutions of science such as the Royal Society, the AAAS, and the rest. Ed cook offered to put a bomb under it in 2003 by telling the truth (in bold), but none of the Hockey Jockeys at the University of East Anglia’s Climate Research Unit wanted to know.

From: Edward Cook <>
To: Keith Briffa <>
Subject: An idea to pass by you
Date: Wed, 3 Sep 2003 08:32:11 -0400
Hi Keith,

After the meeting in Norway, where I presented the Esper stuff as
described in the extended abstract I sent you, and hearing Bradley’s
follow-up talk on how everybody but him has fucked up in
reconstructing past NH temperatures over the past 1000 years (this is
a bit of an overstatement on my part I must admit, but his air of
papal infallibility is really quite nauseating at times), I have come
up with an idea that I want you to be involved in. Consider the
tentative title:

“Northern Hemisphere Temperatures Over The Past Millennium: Where Are
The Greatest Uncertainties?”

Authors: Cook, Briffa, Esper, Osborn, D’Arrigo, Bradley(?), Jones
(??), Mann (infinite?) – I am afraid the Mike and Phil are too
personally invested in things now (i.e. the 2003 GRL paper that is
probably the worst paper Phil has ever been involved in – Bradley
hates it as well), but I am willing to offer to include them if they
can contribute without just defending their past work – this is the
key to having anyone involved. Be honest. Lay it all out on the table
and don’t start by assuming that ANY reconstruction is better than
any other.

Here are my ideas for the paper in a nutshell (please bear with me):

1) Describe the past work (Mann, Briffa, Jones, Crowley, Esper, yada,
yada, yada) and their data over-laps.

2) Use the Briffa&Osborn “Blowing Hot And Cold” annually-resolved
recons (plus Crowley?) (boreholes not included) for comparison
because they are all scaled identically to the same NH extra-tropics
temperatures and the Mann version only includes that part of the NH
(we could include Mann’s full NH recon as well, but he would probably
go ballistic, and also the new Mann&Jones mess?)

3) Characterize the similarities between series using unrotated
(maybe rotated as well) EOF analysis (correlation for pure
similarity, covariance for differences in amplitude as well) and
filtering on the reconstructions – unfiltered, 20yr high-pass, 100-20
bandpass, 100 lowpass – to find out where the reconstructions are
most similar and different – use 1st-EOF loadings as a guide, the
comparisons of the power spectra could also be done I suppose

4) Do these EOF analyses on different time periods to see where they
differ most, e.g., running 100-year EOF windows on the unfiltered
data, running 300-year for 20-lp data (something like that anyway),
and plot the 1st-EOF loadings as a function of time

5) Discuss where the biggest differences lie between reconstructions
(this will almost certainly occur most in the 100 lowpass data),
taking into account data overlaps

6) Point out implications concerning the next IPCC assessment and EBM
forcing experiments that are basically designed to fit the lower
frequencies – if the greatest uncertainties are in the >100 year
band, then that is where the greatest uncertainties will be in the
forcing experiments

7) Publish, retire, and don’t leave a forwarding address

Without trying to prejudice this work, but also because of what I
almost think I know to be the case, the results of this study will
show that we can probably say a fair bit about extra-tropical NH temperature variability (at least as far as we
believe the proxy estimates), but honestly know fuck-all about what
the >100 year variability was like
with any certainty (i.e. we know
with certainty that we know fuck-all

Of course, none of what I have proposed has addressed the issue of
seasonality of response. So what I am suggesting is strictly an
empirical comparison of published 1000 year NH reconstructions
because many of the same tree-ring proxies get used in both seasonal
and annual recons anyway. So all I care about is how the recons
differ and where they differ most in frequency and time without any
direct consideration of their TRUE association with observed

I think this is exactly the kind of study that needs to be done
before the next IPCC assessment. But to give it credibility, it has
to have a reasonably broad spectrum of authors to avoid looking like
a biased attack paper, i.e. like Soon and Balliunas.

If you don’t want to do it, just say so and I will drop the whole
idea like a hot potato. I honestly don’t want to do it without your
participation. If you want to be the lead on it, I am fine with that



Dr. Edward R. Cook
Doherty Senior Scholar and
Director, Tree-Ring Laboratory
Lamont-Doherty Earth Observatory
Palisades, New York 10964 USA
Phone: 845-365-8618
Fax: 845-365-8152

  1. tallbloke says:

    Nice compendium of climategate emails with commentary here:

    Click to access climategate-emails.pdf

  2. oldbrew says:

    ‘his air of papal infallibility is really quite nauseating at times’

    Not the only one in and around the climate science industry?

  3. Lance Wallace says:

    Oddly enough, a few minutes ago I downloaded a review by Cook, Esper, and d’Arrigo that was published in 2004 (after the email referred to here) and deals with the NH temperate extratropical zone temperatures back to 1000 AD. Here is the abstract. Although it actually mentions the evidence for a “Medieval Warm Period” (thus refuting Mann) it still offers the comforting conclusion that modern temperatures are higher.

    The Northern Hemisphere (NH) temperature reconstruction published by Esper, Cook, and Schweingruber (ECS) in 2002 is
    revisited in order to strengthen and clarify its interpretation. This reconstruction, based on tree-ring data from 14 temperaturesensitive
    sites, is best interpreted as a land-only, extra-tropical expression of NH temperature variability. Its strongly expressed
    multi-centennial variability is highly robust over the AD 1200–1950 interval, with strongly expressed periods of ‘‘Little Ice Age’’
    cooling indicated prior to AD 1900. Persistently above-average temperatures in the AD 960–1050 interval also suggest the largescale
    occurrence of a ‘‘Medieval Warm Period’’ in the NH extra-tropics. However, declining site availability and low withinchronology
    tree-ring replication prior to AD 1200 weakens this interpretation considerably.
    The temperature signal in the ECS reconstruction is shown to be restricted to periods longer than 20 years in duration. After recalibration
    to take this property into account, annual temperatures up to AD 2000 over extra-tropical NH land areas have probably
    exceeded by about 0.3 1C the warmest previous interval over the past 1162 years. This estimate is based on comparing instrumental
    temperature data available up to AD 2000 with the reconstruction that ends in AD 1992 and does not take into account the mutual
    uncertainties in those data sets

  4. greenpete58 says:

    The science is championed by many more than the few you mentioned at the top. Also, “Climategate” occurred eight years ago. The effects of global warming have only exacerbated since then, and the science is still there to document it.

  5. oldbrew says:

    ‘probably exceeded by about 0.31C’
    ‘does not take into account the mutual uncertainties in those data sets’

    Not exactly the end of the world as we know it.

  6. daveburton says:

    Nice find, Tallbloke!

  7. oldbrew says:

    Date: 03/05/17

    The Global Warming Policy Foundation is proud to announce it will screen the UK premiere of the award-winning film The Uncertainty Has Settled in London on 18 May.
    [includes film trailer]