The Greenhouse Metaphor – More Response to Comments

Adding a bit to my earlier response. During an e-mail exchange, I recognized one of my assumptions: Things mix. This is a direct result of the second law of thermodynamics and part of why I was baffled by some of the comments. Gases mix particularly easily; it takes time for solids to dissolve in water, and some liquids don’t mix well, but gases mix very quickly and easily.

In order to separate things, you have to put energy into a system. They don’t separate by themselves unless there is a driving force that overcomes the tendency to mix. In the atmosphere, most of the concentration effects come about either because things haven’t mixed yet (think about the water vapor you see from cooling towers) or because chemistry is producing or destroying them. So the ozone is more concentrated in the ozone layer than in other parts of the atmosphere because sunlight is producing it from the much more plentiful oxygen.

Phila brings up the issue of engaging climate skeptics. I tend to agree with most of what he says, but I’ll give my reasons. He’s made my response easier by excepting my preparation for my lecture, which will largely be attended by those who are not hard-core skeptics. And part of what I’m doing is just trying to understand the issues better for my own satisfaction. I’ve had some questions rattling around in my head that I must clear up before I go before an audience.

Phila divides skeptics into three categories:

In terms of everyday skeptics -- the ones who think that "common sense" disproves this or that aspect of AGW -- I tend to be a bit fatalistic. I think the emotional payoff of not understanding is much larger than the payoff for becoming better informed. I don't think better metaphors and analogies will help, in those cases.

Which makes me wonder, sometimes, how much of the debate is actually necessary. Arguments by "scientific" skeptics tend to contain huge mistakes, but the people who are fooled by them don't care...they're just looking for something that sounds like science.

Meanwhile, amateur arguments are usually based on endlessly rotating misconceptions -- contradictory ones, often. Correct one, and another pops up instantly to take its place. Culturally, this stuff is allied to creationism and it's similarly difficult to argue against.

I’d add that I suspect that some of the skeptics are bound and determined, for purely political or wealth reasons, to take down climate change.

I guess I tend to be a bit of an evangelist for science. I find it ultimately fascinating, and it’s hard for me to believe that others won’t share that fascination if they understand it better. I may not be entirely correct on that, as Phila notes.

But what will be done on climate change will be the outcome of a political struggle. We need to convince the people in the middle that we need to do something. So we need to argue with the skeptics to show we’ve got a case, and we need to make that case well. Recent polls show a dropping-off of support for carbon trading legislation.

Maybe the time we spend arguing with people who can't or don't want to understand would be better spent motivating and encouraging people who either do understand, or are willing to trust the scientific consensus. Maybe that's exactly what skeptics are trying to prevent us from doing.

I think that some are raising objections, the same ones over and over again, to muddy the waters and throw sand in the gears. But I think we need to keep saying stuff that will encourage people, and sometimes that’s replying to the skeptics.