William M. Briggs, Statistician
U.S. Senate Report: Over 400 Skeptical Climate Scientists
January 10th, 2008
The U.S. Senate Committee on Environment & Public Works has
released an addendum to its list of 400-plus scientists who express some level of skepticism about man-made global warming. I highlight this because, well, it turns out that my name has made its way onto the list, so I now have to explain why and what it means to be a “skeptic.”
I should first explain that I am on this list reluctantly, because, as I have been quoted as saying, “Most scientists just don’t want the publicity [associated with speaking out on climate matters] one way or another. Generally, publicity is not good for one’s academic career.” I do not think, then, that my being on that list, and starting this blog, will bring a tremendous boost in my own professional life. Scientists like to see discussions about uncertainty in their methods and results kept inside peer-reviewed journals and not dragged through the press. They have strong opinions on this. Witness the scorn heaped up the physicists Fleishman and Pons when they first released their “cold fusion” theory to the press and not to other scientists; for example, see
this article which says that what the pair did was a “‘classic’ example of what not to do as” scientists. Actually, this is an odd statement because the incident ended well—because it was the initial public announcement that spurred the flurry of research that showed that cold fusion was false.
The only reason that I have been able to think of about why research should be confined to journals is that it is in these places that scientists expect to find new results. Scientists are not in the habit of scanning the newspaper or trolling the internet looking for press releases. There just isn’t the time to do so.
But climatology has, unfortunately, become a different sort of creature. Far too much speculation shows up in the headlines. Prominent scientists have taken to using the press as a bludgeon to discourage reasonable dissent. An example: R K Pachauri, Chairman of the IPCC, and now
co-recipient of the Nobel Peace Prize, has compared anybody that dared question mad-made climate change to those who believe in a flat earth.
“Well, there will always be some skeptics,” Pachauri said. “As you know, there is still in existence something called the Flat Earth Society. There are people — a very limited number, thank God — who believe the Earth is flat.” Source:
Washington Post
These excruciating comments are asinine and irresponsible, and they must be answered publicly.
I am
not skeptical that man causes changes in his environment; in fact, I argue man
must cause changes (see
this post). I am only skeptical about the extent of these changes and about our ability to understand them. I
am skeptical of the results from climate models that are used to posit large and harmful shifts in the earth’s temperature.
The vast majority of pronouncements about climate change are based on
forecasts, guesses made about the future which are conditional on the multitude of assumptions underlying the models being true and on the forecasts having only small error. My specialty is in forecast evaluation (not just climate models, but any kind), and I do not feel that climate models have shown their ability to make accurate predictions thus far. This is why I said that the “error associated with climate predictions is also much larger than that usually ascribed to them; meaning, of course, that people are far too sure of themselves and their models.”
Overconfidence is a common human trait, and it holds in scientists just as much as it does with civilians. Typically, however, the excessive surety of scientists is tempered by the peer-criticism process, which has the effect of reducing, but never eliminating, prediction error. But this service won’t work well if experts are made to feel squeamish about making their critiques because of a public browbeating by autocratic scientists, politicians, and “activists.”
There is also a shade of “groupthink”—bandwagon research—not so much with climatologists, but with the mass of secondary and tertiary investigators who use climate model output as input to their own models of economics, public health, sociology, and so on. These models invariably show what they were programmed to show: that climate change of any kind is bad. This is, of course, physically impossible; but these are not physicists who are making these remarks—which of course quickly find their way into the press—and thus they are not held accountable in that sense.
Of course, if global climate models eventually show skill, then I will believe what they have to say.
