CRU emails No. 11 - response from an unhappy chap

Back in 1997, the CRU was part of a campaign to put together a big list of climate scientists that endorsed the findings of the IPCC. An email was sent out by one Joseph Alcamo from the University of Kassel. Joseph was so keen to get as many names on the list that data quality issues were thrown out the window.

Tom Wigley received the request to endorse a statement to "influence Kyoto". He was not happy with that at all. Tom is a believer, not a skeptic. Read on......

From: Tom Wigley

To: jan.goudriaan@xxxxxxxxx.xxx, grassl_h@xxxxxxxxx.xxx, Klaus Hasselmann , Jill Jaeger , rector@xxxxxxxxx.xxx, oriordan@xxxxxxxxx.xxx, uctpa84@xxxxxxxxx.xxx, john@xxxxxxxxx.xxx, mparry@xxxxxxxxx.xxx, pier.vellinga@xxxxxxxxx.xxx

Subject: Re: ATTENTION. Invitation to influence Kyoto.

Date: Tue, 25 Nov 1997 11:52:09 -0700 (MST)

Reply-to: Tom Wigley

Cc: Mike Hulme , t.mitchell@xxxxxxxxx.xxx

Dear Eleven,

I was very disturbed by your recent letter, and your attempt to get others to endorse it. Not only do I disagree with the content of this letter, but I also believe that you have severely distorted the IPCC "view" when you say that "the latest IPCC assessment makes a convincing economic case for immediate control of emissions." In contrast to the one-sided opinion expressed in your letter, IPCC WGIII SAR and TP3 review the literature and the issues in a balanced way presenting arguments in support of both "immediate control" and the spectrum of more cost-effective options. It is not IPCC's role to make "convincing cases" for any particular policy option; nor does it. However, most IPCC readers would draw the conclusion that the balance of economic evidence favors the emissions trajectories given in the WRE paper. This is contrary to your statement.

This is a complex issue, and your misrepresentation of it does you a dis-service. To someone like me, who knows the science, it is apparent that you are presenting a personal view, not an informed, balanced scientific assessment. What is unfortunate is that this will not be apparent to the vast majority of scientists you have contacted. In issues like this, scientists have an added responsibility to keep their personal views separate from the science, and to make it clear to others

when they diverge from the objectivity they (hopefully) adhere to in their scientific research. I think you have failed to do this.

Your approach of trying to gain scientific credibility for your personal views by asking people to endorse your letter is reprehensible. No scientist who wishes to maintain respect in the community should ever endorse any statement unless they have examined the issue fully themselves. You are asking people to prostitute themselves by doing just this! I fear that some will endorse your letter, in the mistaken belief

that you are making a balanced and knowledgeable assessment of the science -- when, in fact, you are presenting a flawed view that neither accords with IPCC nor with the bulk of the scientific and economic literature on the subject.

Let me remind you of the science. The issue you address is one of the timing of emissions reductions below BAU. Note that this is not the same as the timing of action -- and note that your letter categorically addresses the former rather than the latter issue. Emissions reduction timing is epitomized by the differences between the Sxxx and WRExxx

pathways towards CO2 concentration stabilization. It has been clearly demonstrated in the literature that the mitigation costs of following an Sxxx pathway are up to five times the cost of following an equivalent WRExxx pathway. It has also been shown that there is likely to be an equal or greater cost differential for non-Annex I countries, and that the economic burden in Annex I countries would fall disproportionately on poorer people.

Furthermore, since there has been no credible analysis of the benefits (averted impacts) side of the equation, it is impossible to assess fully the benefits differential between the Sxxx and WRExxx stabilization profiles. Indeed, uncertainties in predicting the regional details of

future climate change that would arise from following these pathways, and the even greater uncertainties that attend any assessment of the impacts of such climate changes, preclude any credible assessment of the relative benefits. As shown in the WRE paper (Nature v. 379, pp. 240-243), the differentials at the global-mean level are so small, at most a few tenths

of a degree Celsius and a few cm in sea level rise and declining to minuscule amounts as the pathways approach the SAME target, that it is unlikely that an analysis of future climate data could even distinguish between the pathways. Certainly, given the much larger noise at the

regional level, and noting that even the absolute changes in many variables at the regional level remain within the noise out to 2030 or later, the two pathways would certainly be indistinguishable at the regional level until well into the 21st century.

The crux of this issue is developing policies for controlling greenhouse gas emissions where the reductions relative to BAU are neither too much, too soon (which could cause serious economic hardship to those who are most vulnerable, poor people and poor countries) nor too little, too late (which could lead to future impacts that would be bad for future

generations of the same groups). Our ability to quantify the economic consequences of "too much, too soon" is far better than our ability to quantify the impacts that might arise from "too little, too late" -- to the extent that we cannot even define what this means! You appear to be putting too much weight on the highly uncertain impacts side of the equation. Worse than this, you have not even explained what the issues are. In my judgment, you are behaving in an irresponsible way that does you little credit. Furthermore, you have compounded your sin by actually putting a lie into the mouths of innocents ("after carefully examining the

question of timing of emissions reductions, we find the arguments against postponement to be more compelling"). People who endorse your letter will NOT have "carefully examined" the issue.

When scientists color the science with their own PERSONAL views or make categorical statements without presenting the evidence for such statements, they have a clear responsibility to state that that is what they are doing. You have failed to do so. Indeed, what you are doing is, in my view, a form of dishonesty more subtle but no less egregious than the statements made by the greenhouse skeptics, Michaels, Singer et al. I find this extremely disturbing.

Tom Wigley