When economists talk about global warming

June 29, 8:02 AMSF Environmental Policy ExaminerThomas Fuller

Previous Next

11 comments Print Email RSS Subscribe

Subscribe

Get alerts when there is a new article from the SF Environmental Policy Examiner. Read Examiner.com's terms of use.

Email Address   Include other special offers from Examiner.com Terms of Use

This week has seen two well-publicized instances of economists offering opinions on global warming.

The one covered in this space was Alan Carlin (although he is also a physicist) who tried to warn the Environmental Protection Agency against relying on research conducted prior to 2005 while evaluating its Endangerment Finding for CO2. (Previous coverage of this can be found here, here, here and here.) Perhaps predictably, the instant response team from the 'warmist' community focused on his lack of credentials in climate science.

Paul Krugman, winner of the Nobel Prize for economics, has also written one article and some blog posts on global warming, found here, here and here. I admire Krugman greatly, especially for his principled stand against the Bush administration's policies, when he was one of the few public figures with the courage to stand up and be counted. To the extent that I understand economics, I tend to agree with his conclusions. However, to the extent that I understand the science of global warming, I disagree with his writing on this subject. I wonder how the people who object to Carlin on the basis of his profession will react to Krugman?

Krugman writes that 'deniers are betraying the planet' referring to the debate last week on the cap and trade bill which narrowly passed through the House of Representatives. Strong language indeed. But he goes on to say,

"To fully appreciate the irresponsibility and immorality of climate-change denial, you need to know about the grim turn taken by the latest climate research.

The fact is that the planet is changing faster than even pessimists expected: ice caps are shrinking, arid zones spreading, at a terrifying rate. And according to a number of recent studies, catastrophe — a rise in temperature so large as to be almost unthinkable — can no longer be considered a mere possibility. It is, instead, the most likely outcome if we continue along our present course."

If these are the reasons he cries treason, he should perhaps reconsider. One ice cap shrunk, as it has before, but is recovering, as it has before. The other ice cap is growing at the rate of 10,000 square kilometers per year. As for deserts, both in China and Africa deserts are actually shrinking. And although MIT computer models did project a potentially high temperature rise for the end of this century, this is disputed by climate scientists, including Richard Lindzen of... MIT. It also is quite different from projections of the IPCC.

In Krugman's blog posts, he excoriates 'deniers' for focusing on short term trends, especially the stabilization of temperatures since 1998. He notes correctly that temperatures have risen since the late 1800s and seems to think that the skeptics ignore that. My reading of what's out there, both on websites and published documents, suggests otherwise.

To me it seems that the skeptic community wants to extend examination of temperature records back to include the Little Ice Age and the Medieval Warming Period, while it is the AGW proponents who want to write them out of the history books, or at least minimize their impacts. (Conventional representation of the Medieval Warming Period indicates it was warmer than current temperatures and many skeptics think the current rise in temperatures is part of a normal recovery from the Little Ice Age.)

I have no doubt that both Krugman and Carlin could improve their writing on the issue of global warming. I have no doubt that both have the intellectual capacity to do a creditable job of analysing this issue. I think for both, what errors I have noticed are due to lack of time to cover the subject more thoroughly, and not anything else.

Most of all, I think efforts to limit the debate to a closed priesthood of scientists is futile and wrong-headed. Scientists receive taxpayer money and are expected to inform policy debate. But nobody will give them the keys to the car--they won't decide policy. So interaction from citizens, politicians and even economists is not only inevitable, it is desirable--it helps shape policy and evaluation of policy mechanisms.

So, Mr. Krugman, I disagree with what you wrote. But not because you're an economist. Not because I don't think you're capable. (And to those AGW proponents who left such kind and temperate comments here over the weekend, if you think that this article is related to my own qualifications to write on this issue, you're probably correct.)