I know, I said that you had likely already heard more than enough about this elsewhere, but this is good.

One of the saddest things for me about climate science is how political it has become. Science works by having an open dialog that ultimately converges on the truth, for the common benefit of everyone. Most scientific fields enjoy this free flow of ideas.

There are serious scientific and technological issues in studying our climate, how it responds to human-caused emission of greenhouse gases, and what the most effective solutions will be for global warming. But unfortunately, the policy implications are vast and there is a lot at stake in economic terms.

It seems inevitable that discussions of climate science would degenerate to being deeply politicized and polarized. Depending on which views are adopted, individuals, industries, and countries will gain or lose, which provides ample motive. Once people with a strong political or ideological bent latch onto an issue, it becomes hard to have a reasonable discussion; once you’re in a political mode, the focus in the discussion changes. Everything becomes an attempt to protect territory. Evidence and logic becomes secondary, used when advantageous and discarded when expedient. What should be a rational debate becomes a personal and venal brawl. Rational, scientific debate that could advance the common good gets usurped by personal attacks and counterattacks.

Political movements always have extremists — bitterly partisan true believers who attack anybody they feel threatens their movement. I’m sure you know the type, because his main talent is making himself heard. He doesn’t bother with making thoughtful arguments; instead, his technique is about shrill attacks in all directions, throwing a lot of issues up and hoping that one will stick or that the audience becomes confused by the chaos. These folks can be found at the fringe of every political movement, throughout all of history.

In short, politics is stupid, as well as being harmful to society. The entertainment value for primates - given that squabbling among themselves about everything and anything is a primary evolved behavior and a key mechanism of social organization - is high but that "benefit" seems to be no where near as great as the costs.

The point I was making to Dubner and Levitt is the following: when you build a solar plant it costs you energy. Lots of energy. Pacca and Horvath, in a 2002 study, found that the greenhouse gas emissions necessary to build a solar plant are about 2.75 times larger than the emissions from a coal plant of the same net power output. . .

Efficiencies of 9 percent to 13 percent are typical for current widely deployed technology. In the future that will change, and some laboratory examples are better, but this is what people deploy now. So for every watt of electricity they generate, current solar cells throw about 10 watts into the climate as heat. Some of this heat would have occurred anyway when the light was absorbed by the ground, but the most effective solar cell installations are in deserts where the albedo is pretty high (.4 to .5) and there is little cloud cover, so the solar cells cause a bunch of heating that would not have otherwise occurred. A typical coal power plant gives off about 2 watts of thermal heat for each watt generated, so the direct thermal heating from solar plants is likely to be as large or larger than that from coal plants. . .

If you mount the solar cells on a rooftop or other surface that is already black or very dark, then it won’t make much of a difference. But, that’s just because the dark surface is already contributing to global warming (two wrongs don’t make a right!), and in any event, most large-scale solar installations are aimed at deserts or other terrain that has pretty high albedo. . .

we need to build out lots of renewable energy if it is going to make a difference. If we finish one plant today, it takes it three years to break even. Three years may not be the exact number, but let’s use it for simplicity. Next year we finish two more plants, and the next year we finish four more plants. Regardless of whether the numbers are 1, 2, 4, or some other sequence, we need to build the increasing amounts if we’re going to get a lot of plants built. But notice this: the three-year break-even times start to overlap and pile up as we build more and more plants.

The net result is that we may not get much CO2 benefit from the solar plants until we are past the rapid-growth phase of building out new plants. If we go hell-bent for leather in building solar plants for the next 50 years or so, it is entirely possible that we won’t see much small benefit for 30 to 50 years. In the long run, we still get benefit from the solar plants — lots of benefit (hence the “great carbon-free infrastructure”) — but in the near term, we may get little or no benefit. I say “may” because the details matter . . .

This isn't an argument against moving toward greatly expanded use of solar cells for power generation, it's a realistic analysis of the expected costs and benefits over time. This is precisely how to make good decisions, but it isn't how to do mob politics since it deflates zeal. It's too sober and sensible to be useful to those who seek nothing more than to incite mobs to march around with their fists in the air. The goal of mobocrats isn't to implement good policies, it is only to incite the mob and ride their unthoughtful zeal to power and personal advancement.

This kind of attack makes it very difficult for people to suggest new ideas. I have thick enough skin to laugh it off when Romm attacks me, but plenty of people don’t. The politicization of science has a terrible impact on the unfettered discourse of ideas that is so important to making progress. This has been a big impediment to geoengineering. Serious climate scientists who are privately interested in geoengineering are loathe to discuss it publicly because they worry that somebody like Romm will attack and ridicule them if they do. Indeed, part of the reason I chose to work on geoengineering and chose to go public about it is to try to get the topic to be more widely discussed.

The point of the chapter in SuperFreakonomics is that geoengineering might be good insurance in case we don’t get global warming under control. Nobody can tell you today exactly how much CO2 we can emit without causing grave environmental harm. Nobody can tell you at what point the world will find the political will, the money, and the technological innovation to solve the problem. In a situation like that, can the world afford to turn its back on what could be a promising approach should we fail with our other efforts?

That’s the question that SuperFreakonomics asks, and that is the question on which we should be focused.

This is an important point, one that has wider applicability since it isn't only climate issues that are degraded by politicization. For example, one of my pet concerns has been the retardation of agricultural progress due to political zealotry, though the need for increased output from agriculture is great due to continuing population growth. As with climate, political will is of little or no relevance when you analyze the threats and possible mitigations in a clear eyed manner. Politics is an expensive and harmful distraction, part of the problem set rather than the solution set.