Articles by Andrew Dessler

Skeptical about skeptics

One last comment on NASA administrator Michael Griffin's comments about global warming. The skeptics out there heralded his comments. For example, Bob Carter was quoted as saying, "My main reaction to Michael Griffin is to congratulate him on his clear-sightedness, not to mention his courage in speaking out on such a controversial topic."

What these skeptics seem to forget (or conveniently ignore) is that Griffin's comments were only about the moral question of whether we should address climate change, not about the reality of human-induced climate change. From the New York Times: "In his comments to NPR and in today's interview, he did not express any doubt that the warming trend is real or that humans have been found to play a part in that rise." Skeptics never comment on this aspect of Griffin's statement.

This is a good example of why skeptics cannot be trusted. A skeptic would only tell you the point about Griffin's questioning the moral aspect of climate change policy, and conveniently forget to tell you that Griffin specifically endorses the dominant scientific view that humans are warming the world. Remember that next time you hear a skeptical statement about climate change.

Recent report published projecting values of sea-level rise

As anyone who reads my posts knows, I am a big fan of the IPCC reports. They are the best summary of what the scientific community knows about climate change and how confidently we know it.

A recent article (subscription required, sorry) in Science suggests that some scientists view the IPCC as overly cautious:

In the latest report, its fourth since 1990, the IPCC spoke for scientists in a calm, predictably conservative tone (Science, 9 February, p. 754). It is, after all, an exhaustive, many-tiered assessment of the state of climate science based exclusively on the published literature. In IPCC's Working Group I report on the physical science of climate, 600 authors contributed to an 11-chapter report that drew 30,000 comments from reviewers. The report was in turn boiled down to a 21-page "Summary for Policymakers" (SPM). Its central projection of sea-level rise by the century's end -- 0.34 meter -- came within 10% of the 2001 number. And by getting a better handle on some uncertainties, it even brought down the upper limit of its projected range, from 0.89 to 0.59 meter.

The SPM did add that "larger values [of sea-level rise] cannot be excluded." Whatever has accelerated ice-sheet flow to the sea, the report said, might really take off with further warming -- or not. "Understanding of these effects is too limited" to put a number on what might happen at the high end of sea-level rise, it concluded. Lacking such a number, the media tended to go with the comforting 0.34-meter projection or ignore sea level altogether.

I have two conflicting views of this.

A new idea for how to transport the stuff in cars

I have never been a fan of hydrogen technology as a solution to the climate change problem. It would be great if we could power automobiles with hydrogen (generated, of course, with renewable energy), but how do you carry the hydrogen around in your car? Do you really want to be driving around on top of a tank full of compressed hydrogen? Can you say Hindenburg?

I just listened to a great segment on this week's Science Friday. The guest, Jerry Woodall, a professor at Purdue, has an interesting idea for how to carry hydrogen in a way that seems extremely safe to me.

The idea is that you carry around a bunch of aluminum. You react the aluminum with water, and that produces hydrogen, which would then be immediately burned. In the end, you're left with a tank full of aluminum oxide, which will be recycled back into aluminum (using, of course, renewable energy) at a recycling facility.

This seems like a great idea, one that makes me reconsider my skepticism towards hydrogen. But listen to the segment yourself. Also, check out the presentations on this site.

On the NASA administrator’s comments

Michael Griffin is a highly educated guy. He has five Masters degrees (count 'em: aerospace science, electrical engineering, applied physics, business administration, and civil engineering) and a Ph.D. in aerospace engineering (see here).

However, his interview on NPR shows that all that book learnin' doesn't mean what he says is intelligent.

For a recap of the high points of the interview, see David's post. I'm going to talk in this post about what makes our climate optimal.