Articles by Andrew Dessler

Flawed new analysis purports to show that there’s no scientific consensus on climate change

If those opposed to action on climate change are like Ahab, the scientific consensus is their white whale. The reason is simple: as Frank Luntz's famous memo pointed out, if they can convince the general public that the science of climate change is uncertain, they can drag the debate over policy to a grinding halt.

Thus, every so often, another argument emerges that purports to prove that scientific consensus on climate change does not exist.

This week, it's a blast from the past: an analysis of the "Web of Science" that shows that no consensus exists and only a minority of scientists support the views of the Intergovernmental Panel on Climate Change (IPCC).

First, some background. For those who aren't familiar, the Web of Science (WoS) is a massive database that includes the title and abstract of essentially every scientific paper published since the early '90s. There's also a ton of ancillary information in the database, such as how many times a paper has been cited. It's an invaluable tool to the scientific community, one I use on an almost daily basis to find papers in the peer-reviewed literature.

Naomi Oreskes, a Professor of History and Science Studies at UC-San Diego, searched WoS for papers that include the phrase "global climate change" in the title or abstract and found that basically none of these papers explicitly reject the consensus position (i.e., the earth is warming, humans are very likely responsible for most of the recent warming, etc.). See Coby Beck's writeup for more details.

A medical researcher, Dr. Klaus-Martin Schulte, has revisited Oreskes' analysis. Oreskes looked at papers published between the mid-1990s and 2003, while Schulte looked at papers published after 2004. I have not actually seen a copy of this new paper, but I've reconstructed its salient points from a description of the analysis found here (PDF). The abstract of Dr. Schulte's paper:

Fear of anthropogenic 'global warming' can adversely affect patients' well-being. Accordingly, the state of the scientific consensus about climate change was studied by a review of the 539 papers on "global climate change" found on the Web of Science database from January 2004 to mid-February 2007, updating research by Oreskes (2004), who had reported that between 1993 and 2003 none of 928 scientific papers on "global climate change" had rejected the consensus that more than half of the warming of the past 50 years was likely to have been anthropogenic. In the present review, 32 papers (6% of the sample) explicitly or implicitly reject the consensus. Though Oreskes said that 75% of the papers in her sample endorsed the consensus, fewer than half now endorse it. Only 7% do so explicitly. Only one paper refers to "catastrophic" climate change, but without offering evidence. There appears to be little evidence in the learned journals to justify the climate-change alarm that now harms patients.

This analysis is rubbish. First, consider the following abstract, from a paper entitled, "An analysis of the regulation of tropical tropospheric water vapor":

Thoughts on Chris Mooney’s Storm World

I recently finished Chris Mooney's great new book Storm World. There have been lots of reviews (see Chris's blog for a pretty complete list), so I won't write another one here. Instead, I thought I would highlight the part I particularly appreciated, and what I think needed more emphasis in the book.

First, the high point: The book does a great job of detailing the turbulent interface between knowledge and ignorance where science operates. Science is a contact sport, and it is not for the faint of heart. New ideas, especially bold ones, have to survive in the crucible of science -- where they are subject to bombardment by every imaginable criticism. Good ideas survive this test and help us push back the frontiers of knowledge. Bad ideas crumble.

On the other hand, one of the points that I thought could have been better explained was the unique role that Bill Gray played in the debate. All scientists, regardless of their true motivation, want to be seen dispassionately pursuing truth. And in order to do that, it is generally accepted practice that scientists never personally attack other scientists. At least, not in public. You might believe that a scientific competitor of yours is a dishonest scumbag and a hack, and you might even tell a close colleague in private, but you would never, ever stand up at a scientific meeting and say that. It is simply not done.

Thoughts on the GISS temperature adjustment

There has been a lot of blogging recently about the problem with the temperature record for the continental U.S. RealClimate described the problem thusly:

Last Saturday, Steve McIntyre wrote an email to NASA GISS pointing out that for some North American stations in the GISTEMP analysis, there was an odd jump in going from 1999 to 2000. On Monday, the people who work on the temperature analysis (not me), looked into it and found that this coincided with the switch between two sources of US temperature data. There had been a faulty assumption that these two sources matched, but that turned out not to be the case. ...

The net effect of the change was to reduce mean US anomalies by about 0.15 ºC for the years 2000-2006. There were some very minor knock on effects in earlier years due to the GISTEMP adjustments for rural vs. urban trends. In the global or hemispheric mean, the differences were imperceptible (since the US is only a small fraction of the global area).

A few comments about this:

How the two are related

Science Friday recently had a great segment on cognitive dissonance, defined as:

A psychological term which describes the uncomfortable tension that may result from having two conflicting thoughts at the same time, or from engaging in behavior that conflicts with one's beliefs.

Because it is uncomfortable, your brain will seek out ways to resolve the contradictions.

So if you think you're a good and moral person, but you fudge a little on your taxes, you might justify this with an excuse like: "I've overpaid in previous years," or "the government is using my money in an immoral way," or "everyone else is doing it."

New research shows that this is not some individual character flaw, but a strong and consistent human impulse. Brain scans show that the brain floods with pleasure when conflicting ideas are resolved.

I thought the segment went a long way toward explaining why skeptics on global warming still exist. When presented with conflicting views, such as "I am a good person" vs. "my lifestyle is destroying the planet," the brain comes up with a way to resolve them, such as, "global warming is a conspiracy cooked up by celebrities and scientists."

This really highlights why we need to emphasize solutions. If we give people ways to address the problem, they won't need to deny it.