The May/June issue of American Scientist has an article by David Schneider on the IPCC/Landsea flap that offers some new comments from the principals involved in that controversy. And I again bring up this issue because hurricane season is right around the corner, when this debate might threaten to come out of its springtime dormancy. The good news is that this controversy need not continue, and the new comments suggest a rapprochement.

Many Prometheus readers will recall that last January NOAA’s Chris Landsea resigned as a contributor to the IPCC after receiving an unsatisfactory response from the IPCC related to his to his concerns that the author (Kevin Trenberth) of the forthcoming IPCC chapter that summarized the science of hurricanes had made statements at a press conference unsupportable in the scientific literature (you can find a number of posts on this issue in the Prometheus archives, and here is one post that might be a good intro).

Schneider reports in American Scientist,

“Trenberth now says that “it was clear [in the press conference] I was not speaking for the IPCC.” Yet the moderator for the briefing had introduced Trenberth as “convening lead author of the 2007 Intergovernmental Panel on Climate Change report.” And in his opening remarks Trenberth volunteered, “I was a lead author on the 2001 IPCC report for Working Group One, which deals with the science of climate change, and in fact I was involved in developing some of the information that is in that report dealing with hurricanes.””

Schneider also reports of Landsea, “[Landsea said] “If I had to make a guess for the next 20 years, I’d say it’s going to be a lot like the last 10 years.” That is not to say that Landsea discounts any influence of a warming planet. “No one should pooh-pooh the possibility that global warming might do bad things,” he says. But he stresses that the increase in hurricane wind strength being suggested on the basis of computer modeling is “pretty tiny.” And he points out that the monitoring of hurricane winds today has a coarseness of about 5 miles per hour. So the influence of global warming on hurricanes now, if it exists at all, is in the noise. “Even in 2080,” he says, “you might not be able to measure it.””

[Schneider also discusses Hans von Storch in the article, which is online here.]

So Trenberth appears to accept that it is a good idea to keep separate the IPCC perspective from that of individual scientists. For his part, Landsea states both an expectation that coming decades will be more active than the long term average and leaves open the possibility of global warming influencing hurricanes (in a “tiny,” undetectable fashion). If these comments are reported accurately then we should be able to get through hurricane season 2005 with out replaying the debate over global warming and hurricanes. (I can imagine the laughter at my naiveté!)

More generally for the role of scientists and leadership in the IPCC, these new comments from Trenberth and Landsea reinforce my own perspective on how this controversy might have been avoided — “[H]ad Trenberth instead said at that now infamous Harvard press conference, “The IPCC concluded X, Y, and Z about hurricanes in its 2001 assessment, but my personal view is A, B, and C,” then I be willing to bet that there would have been no Landsea/IPCC flap.” And to be fair to Kevin, the IPCC leadership easily could have avoided this controversy after the comments had been made with even a half-hearted effort to respond seriously to Landsea’s complaints. On this I wrote, “The IPCC should either ask scientists to refrain from using their IPCC affiliation when making scientific claims that are inconsistent with the IPCC, or conversely, when scientists use their IPCC affiliation to burnish their credentials they should be sure to clearly identify the IPCC’s position on the topic being discussed. To do otherwise is to invite the politicization of the IPCC process.”