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Re: News Advisory: Still Crazy After Oil These Years!



(Harold Brashears) wrote:
: There has been considerable
: controversy about the latest report.  The scientists who wrote the
: report claim that after they read and ok'ed the final version, the
: document was changed to make it appear as if everyone had agreed that
: the earth was in imminent danger.  Danger which requires immediate
: action.  This is now a political, not a scientific statement.  See the
: WSJ of the last 3 weeks for the ongoing reports.

  Harold is telling a lie here.   There is no "considerable
controversy", but no doubt Harold would like to promote one.

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.
-- 
Paul Farrar
http://www.datasync.com/~farrar/
farrar@datasync.com
70053,3464

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