Would you classify the summary as not a summary, but a meta-analysis? A
meta-analysis is an approach in which multiple studies are jointly analyzed
in order to reach a stronger conclusion than anyone of them. I've primarily
seen it in biostatistics--for instance, multiple studies under varying
conditions may show a suggestive link between, say, vitamin X intake and
improved heart function, but statistical significances of that factor among
the studies vary from 0.35 (not statistically significant) down to 0.03
(highly significant). A rigorous meta-analysis would encode the differences
between studies and reanalyze the original data; and casual meta-analysis
would combine the point estimates and standard deviations of factor effects
to get an overall statistical significance.
We have generated three versions of summaries here:
(1) A "true" summary summarizing the report, presenting only results that
are contained in at least one of the reports, but not drawing any
conclusions beyond a recitation of the facts.
(2) An "advocacy" summary that reflects "what everybody knows" (or the
party line, or the pseudo-consensus) and not the report. (Seitz's claim)
(3) A "meta-analysis" summary that analyzes the report's composite studies
for commonalities and likely conclusions. (My suspician)
Another caveat: So far we have been discussing what Seitz has said about the
report summary. While Seitz may be emminant, he may also be wrong or biased
or deceived--in short, is promoting his own agenda. Shall we be innocent as
doves & wary as serpents?
What says the equally emminant scientists who have been attacked by Seitz?
Namely, Dr. Benjamin Santer of Lawrence Livermore National Laboratory.
I have finally read Seitz's article in the Wall Street Journal, a related
article "Doctoring the Documents? Revisions to key report understate climate
change uncertainties" (by Dennis Wamsted, in the Energy Daily), a rebuttel
by Santer, and a New York Times article. As expected, they have a different
perspective--and it is clear that this is not a simple matter of changing
the results from truth to falsehood (as Seitz implies).
I have attached the core of Sander's rebuttal to Wamsted's article. I can
send e-mail copies of these articles to anyone interested. They're somewhat
lengthly, so it would be rude to dump them all on everyone indiscriminantly.
A few points:
First, the bottem line summary of the report never changed. "The balance of
evidence suggests that there is a discernible human influence on global
climate.".
Second, the changes were in response to review comments or in order to
clarify scientific points. Anyone who has edited technical writing to make
it clear to non-scientists can appreciate that necessity of clarity!
Third, apparently the major change providing gist for Seitz's mill was the
removal of the concluding summary from Chapter 8--which was redundant
because there was also an up front executive summary. The removed material
was incorporated into the rest of chapter 8, or was redundant to start with.
Fourth, Dr. Seitz is associated with the Global Climate Coalition, which is
an fossil fuel industry group committed to do downplaying climate change.
Another consortium of energy interests, The World Energy Council, reaches a
different conclusion: "The IPCC's reputation rests upon its scientific
objectivity, excellence and balance and it must not run ahead of the game if
its reputation is to be safeguarded. The careful reader will judge the
IPCC's SAR to have retained scientific integrity".
Fifth, Seitz never approached Santer for an explaination of the changes.
Of course, it would also be nice to have a feedback from christians on the
IPCC committee, not that we can establish truth by counting christian noses
on either side of issues. Fortunately, the Times article quotes Dr. John
Houghton, an evangelical, and co-chairman of the working group that prepared
the scientific report of the IPCC.
Meanwhile,, an opposing view of Dr. Seitz's article held
that it "just hasn't any basis in fact at all." And the lobbying group's
contentions are "just rubbish," said Dr. John Houghton, a Briton who is a
co-chairman of the working group that prepared the scientific report of the
Intergovernmental Panel on Climate Change, ....All the accusations, Dr.
Houghton said, are based on a draft, dated last Oct. 9, of the report's
chapter on the detection of human-induced climate change. Before and during
the Madrid meeting in late November, he said, many comments on the draft and
many suggestions for changes were received by the chapter's designated
leading author, Dr. Benjamin D. Santer of the Lawrence Livermore National
Laboratory in California. In effect, Dr. Houghton said that these exchanges
constituted the final stage of peer review for the chapter.
My thumbnail conclusion is--after reviewing the articles by Seitz, Wamsted,
Santers, and the New York times--that Seitz & the Global Climate Coalition
are the villians here, by selectively taking items out of context in order
villify the scientists who disagree with them, and to distract policy makers
from the overall conclusions of the IPCC report (especially since a rational
review of the data does not support their purposes).
Here is Santer's rebuttal:
_________________________
COVERING LETTER TO ENERGY DAILY: June 3, 1996
Dr. Benjamin D. Santer PCMDI, Lawrence Livermore National Laboratory P.O.
Box 808, Mail Stop L-264 Livermore, CA 94550 Tel: (510) 423-4249 FAX: (510)
422-7675 email: bsanter@rainbow.llnl.gov
The Editor Energy Daily 627 National Press Building Washington D.C. 20045
Dear Sir,
We would like to respond to an article that was published in Energy Daily on
May 22, 1996. The article, by Dennis Wamsted, was entitled "Doctoring The
Documents?" and deals with alleged improprieties on the part of the Lead
Authors of Chapter 8 of the 1995 Report by Working Group I of the
Intergovernmental Panel on Climate Change (IPCC). The principal allegations
are that unauthorized changes were made to this chapter after an IPCC
meeting held in November 1995 in Madrid, and that important scientific
uncertainties were suppressed. These allegations are apparently based on
material supplied to Mr. Wamsted by the Global Climate Coalition (GCC).
The allegations are serious. It may be that Mr. Wamsted thought they were
well-founded on the basis of the material supplied by the GCC, but this is
incorrect. We believe that Mr. Wamsted should at the very least have
contacted one of the Lead Authors of Chapter 8 in order to obtain a more
balanced view of how and why revisions were made to this chapter. We feel
sure that Energy Daily is dedicated to balanced and factually correct
reporting. To ensure that this balance is restored, and that the
misinterpretations, misconceptions, and factual errors in Mr. Wamsted's
article are corrected, we request that Energy Daily publish our extended
reply.
As supporting information, we are enclosing the now-published version of
Chapter 8, together with excerpts from a review of the full 1995 IPCC Second
Scientific Assessment by the World Energy Council.
Sincerely,
Dr. Benjamin D. Santer Convening Lead Author of Chapter 8 of 1995 IPCC
Working Group I Report
_______________________________________________________________________
REPLY TO ENERGY DAILY ARTICLE: JUNE 3, 1996
We would like to respond to an article that was published in Energy Daily on
May 22, 1996. The article, by Dennis Wamsted, was entitled "Doctoring The
Documents?" and deals with alleged improprieties on the part of the Lead
Authors of Chapter 8 of the 1995 Report by Working Group I of the
Intergovernmental Panel on Climate Change (IPCC). This Report is a
comprehensive assessment of the scientific information on climate change,
involving hundreds of scientists worldwide. The chapter in question
evaluates the scientific evidence from studies that have attempted to detect
significant climate change and determine whether some portion of that change
can be attributed to human activities.
Mr. Wamsted's article relies on information from the Global Climate
Coalition, which he characterizes as "a group of U.S. businesses opposing
immediate action to reduce greenhouse gas emissions". The Global Climate
Coalition alleges that:
* Unauthorized changes were made to Chapter 8 ("The key document outlining
the scientific backing for global climate change has been rewritten without
proper authority", writes Mr. Wamsted).
* Scientific uncertainties were suppressed (The revised chapter, according
to Mr. Wamsted, "soft-pedals the uncertainties". He further asserts that
"The only remaining uncertainty, the revised chapter contends, is the
magnitude of the (human-induced) change").
Mr. Wamsted then gives a number of specific examples that purportedly
support these serious allegations. We show below that these allegations are
baseless.
At the beginning of October 1995, a draft of the Summary for Policymakers
(SPM), together with all eleven chapters of the 1995 IPCC Working Group I
Report, was circulated to governmental and non-governmental participants of
an IPCC meeting that was to be held in Madrid from November 27-29th, 1995.
The primary goal of the Madrid meeting was to modify where necessary, and
then formally approve the SPM, and to accept the eleven scientific chapters.
The circulated chapters were dated October 9th, 1995.
It is true that changes were made to Chapter 8 after the Madrid meeting.
However, these changes did not circumvent procedural rules. As is required
by IPCC procedures, changes were made in direct response
TO:
* Written comments made by governments and non-governmental organizations
(NGOs) during October and November 1995;
* Comments made by governments and NGOs during the plenary sessions of the
Madrid meeting. These comments helped to identify specific problems with the
clarity of the text of Chapter 8, leading to misinterpretation of some of
the scientific statements. Such problems were a natural outcome of the
difficulties encountered in conveying complex scientific ideas to lay
persons.
Post-Madrid changes to Chapter 8 were made solely in response to review
comments and/or in order to clarify scientific points. None of the changes
were politically motivated. The suggestion by the Global Climate Coalition
that this was the case is entirely wrong. All revisions were made with the
sole purpose of producing the best-possible and most clearly-explained
assessment of the science, and were under the full scientific control of the
Convening Lead Author of Chapter 8.
Did the changes alter the substance of the scientific conclusions of Chapter
8, as the Global Climate Coalition has alleged? The answer is categorically
no. The evaluation of the scientific evidence in Chapter 8 was the same
before and after the Madrid meeting. The bottom-line assessment of the
science in the Oct. 9th version of Chapter 8 was "Taken together, these
results point towards a human influence on climate". The final assessment in
the now-published Summary for Policymakers is that "the balance of evidence
suggests that there is a discernible human influence on global climate". The
latter sentence, which is entirely consistent with the earlier Oct. 9th
sentence, was unanimously approved at the Madrid meeting by delegates from
nearly 100 countries.
Did the Lead Authors of Chapter 8 engage in "scientific cleansing" as the
Global Climate Coalition have alleged, and purge material that would have
tended to highlight uncertainties? Here, too, the answer is no. Over
four-and-a-half pages of Chapter 8 are specifically devoted to the
discussion of uncertainties in estimates of natural climate variability and
the expected "signal" due to human activities. The remaining text abounds
with caveats and discussions of other uncertainties.
Uncertainty is an integral part of the climate change detection and
attribution problem, and the discussion of uncertainty is an integral part
of the main text and executive summary of Chapter 8. Mr. Wamsted could not
be further from the truth with the claim that "The only remaining
uncertainty, the revised chapter contends, is the magnitude of the change".
The only plausible explanation for this statement is that Mr. Wamsted had
not read the published version of Chapter 8 before writing his article, and
relied solely on information supplied by the Global Climate Coalition.
A major concern of the Global Climate Coalition, reports Mr. Wamsted, is
that the "Concluding Summary" (Section 8.7) in the Oct. 9th version of
Chapter 8 has now been removed. The Oct. 9th version of Chapter 8 was the
only chapter in the 1995 IPCC WG I report to have both an executive summary
up front and a concluding summary. After receiving much criticism of this
redundancy in October and November 1995, the Convening Lead Author of
Chapter 8 decided to remove the concluding summary. About half of the
information in the concluding summary was integrated with material in
Section 8.6. It did not disappear completely, as the Global Climate
Coalition has implied. The lengthy Executive Summary of Chapter 8 addresses
the issue of uncertainties in great detail - as does the underlying Chapter
itself.
Clearly, it is beyond the scope of this letter to give the full scientific
justification for each of the changes Mr. Wamsted mentions. Chapter 8 deals
with a complex scientific issue, and it is easily possible to consider
individual changes out of the scientific context in which they occur. One
crucial example highlights the problem. Mr. Wamsted, apparently using the
Global Climate Coalition's analysis of Chapter 8 as a source, quotes the
following sentences from the Oct. 9th version of Chapter 8:
"Finally, we come to the most difficult question of all: When will the
detection and unambiguous attribution of human-induced climate change occur?
In the light of the very large signal and noise uncertainties discussed in
this Chapter, it is not surprising that the best answer to this question is,
`We do not know'."
He then contrasts this with the corresponding statement in the now-published
chapter:
"Finally, we come to the difficult question of when the detection and
attribution of human-induced climate change is likely to occur. The answer
to this question must be subjective, particularly in the light of the large
signal and noise uncertainties discussed in this chapter. Some scientists
maintain that these uncertainties currently preclude any answer to the
question posed above."
Unfortunately, Mr. Wamsted's quote ends here, thus conveying the erroneous
impression that "We do not know" has been swept under the carpet. Had he
continued, he and his readers would have received a more balanced impression
of the changes made. In fact, the next sentences read as follows:
"Other scientists would and have claimed, on the basis of the statistical
results presented in Section 8.4, that confident detection of a significant
anthropogenic climate change has already occurred. As noted in Section 8.1,
attribution involves statistical testing of alternative explanations for a
detected observed change, and few would be willing to argue that completely
unambiguous attribution has already occurred, or was likely to happen in the
next few years".
Why were changes made here? Throughout the text of Chapter 8, "detection"
and "attribution" are defined and handled separately. Detection involves
showing that some observed climate change is unusual, while attribution is
the process of demonstrating cause and effect. The Oct. 9th statement quoted
above lumped detection and attribution together. This was clearly confusing
to some of the participants at the Madrid meeting. The revision considers
detection and attribution separately in trying to answer the "when can we
expect" question. This is more in line with the rest of the chapter. The
changes are a more accurate reflection of the currently diverse scientific
opinion - some scientists say we've already detected significant climate
change, others say that we can't claim detection at present, and both sides
concur that unambiguous attribution hasn't happened yet.
The Global Climate Coalition - a less than disinterested party - has made
serious allegations regarding the scientific integrity of the Lead Authors
of Chapter 8, and of the IPCC process itself. We are troubled that Mr.
Wamsted did not consult with the Lead Authors of Chapter 8 or with members
of the IPCC Working Group I Technical Support Unit before writing his
article. Had he done so, he would have gained a better understanding of how
and why changes were made to Chapter 8.
Finally, we refer to an alternative assessment of the full 1995 IPCC Second
Scientific Assessment by the World Energy Council. Like the Global Climate
Coalition, the World Energy Council is also a consortium of energy
interests. The similarity ends there. The World Energy Council and Global
Climate Coalition reach very different conclusions regarding the scientific
balance of the post-Madrid version of Chapter 8, and the extent to which it
accounts for important uncertainties. We are encouraged that the World
Energy Council makes the following statements regarding the 1995 IPCC
report:
"It is important that commentators on the IPCC SAR's (Second Assessment
Report's) discussion of human influence on global climate do not run ahead
of the evidence and of what the SAR actually says, and fail to note
sufficiently well the references to ongoing uncertainty".
"The IPCC's reputation rests upon its scientific objectivity, excellence and
balance and it must not run ahead of the game if its reputation is to be
safeguarded. The careful reader will judge the IPCC's SAR to have retained
scientific integrity".
The published version of Chapter 8 is the best possible evaluation of the
evolving scientific evidence. It was produced by a process that rigorously
adhered to the procedural guidelines laid down for the production of IPCC
reports and to the scientific principles of openness, honesty and peer
review. We would encourage Mr. Wamsted and others to read Chapter 8 and
form their own opinions on the scientific justification for its conclusions,
and not to rely solely on views espoused by the Global Climate Coalition.
Benjamin D. Santer Convening Lead Author, Chapter 8 of 1995 Working Group I
IPCC Report Program for Climate Model Diagnosis and Intercomparison Lawrence
Livermore National Laboratory Livermore, CA 94550 U.S.A
Tom M.L. Wigley Lead Author, Chapter 8 of 1995 IPCC Working Group I Report
National Center for Atmospheric Research Boulder, CO 80307-3000 U.S.A.
Tim P. Barnett Lead Author, Chapter 8 of 1995 IPCC Working Group I Report
Scripps Institution of Oceanography University of California La Jolla, CA
92093 U.S.A.
Ebby Anyamba Lead Author, Chapter 8 of 1995 IPCC Working Group I Report
NASA/Goddard Space Flight Center Greenbelt, MD 20770 U.S.A.