Monday, April 13, 2009
A really awe-inspiring TED talk by David Deutsch is also really discouraging and disappointing.
Of course at first I didn't see where he was going. Unfortunately he was leading up to some fundamentally cracked ideas about climate change. It's really sad, as the talk is inspiring and invigorating until it gets to the hopelessly wrong parts. But what is it about physicists that gives them license to get the climate problem so dramatically and publicly wrong while putting so little effort into investigating it?
Deutsch concludes that we should focus on fixing big problems, not on avoiding them. This is a commonly held opinion by smart people who don't understand the climate problem. It's fundamentally wrong on two grounds. First, as he in effect points out, there really isn't a strong distinction between avoiding a problem and solving a problem; avoiding a problem is a version of solving a problem, isn't it? Second, of course, the extent to which you have a problem isn't binary. You may have a big climate change problem, or a huge one, or an overwhelming one. And of course, all the exciting progress he goes on about, all this capacity to "create the relevant knowledge" suddenly goes away once problems become overwhelming. Perhaps people whose immediate family have never actually been in overwhelming situations are overly sanguine about this possibility.
Those are just the gross failures of his position. Now onto the deatils.
He only talks about climate change for three minutes, after leading up to it for fifteen, but look at the holwers he manages to come up with in those three minutes.
1) "It's already too late to prevent a catastrophe" is true in some weak sense, but again, the situation isn't binary. It is the scope of the catastrophe that is exactly what is at issue.
2) "The actions proposed don't solve the problem, but merely postpone it by a little". That was true of Kyoto, the advantage of which would have been that we would have international protocols in place now that the real cuts are needed. Having skipped that step, our job is more difficult. But 80% cuts in the advanced countries by 2050 are at least consistent with addressing the problem at scale, and that is what we are discussing nowadays. In fact, that is the only sane recourse.
3) "in the 1970's when the best science was warning about humans causing an ice age". Groan.
4) "When we know how to avoid a disaster at a cost that's much less than the disaster being avoided, there's not going to be much argument, really." You'd think. But, alas, no. I refer Dr. Deutsch to an interesting blog called Only In It for the Gold which is centrally focussed on why this fairly obvious "fact" just isn't true. (Hint: what is "known" to science greatly exceeds what is "known" to policy.)
5) "Instead of reducing gases we ought to be looking at plans to reduce the temperature". This is geoengineering idiocy. It is really necessary to get a couple of very fundamental facts across. First: the problem is not the temperature, it is the rearrangement of the fluid flow regimes in the new temperature regime. Temperature is only a crude gauge of climate change. We can have massive climate change with small changes in global mean temperature, though the case of small climate change with large temperature changes is excluded. This is where the actual scientific knowledge comes in. And though Deutsch claims to defer to the experts, it appears he has not bothered to talk to any of them.
6) He also briefly mentions an approach to carbon sequestration and then proceeds to a broad brush characterization that "nobody" is thinking seriously about these things. Of course that's a very sweeping generalization, and I think it's actually not true at all in the actual scientific sectors where the work is happening. Of course, the left and the right may not be paying any mind, so of course the press isn't either. But I'd hope a physicist talking informally about the subject would know better, and I'd insist that a physicist talking publicly about it take the time to actually meet and talk to people working in the field.
So six substantial objective errors of fact in three minutes in a public talk.
Finally, let me point out that his arguments are totally disjoint from economics or politics. I sympathize. I like to start from what's physically possible, proceeding thence to what is socially and economically possible. Deutsch ignores that problem altogether. I suppose that is better than the opposite position which ignores physics in favor of politics, but not by much.
Again, there's much that I very much enjoyed about the talk so I'm sorry to have to say it's irresponsible. Indeed it is irresponsible in a very Dysonesque way. Why do physicists with their perspective on the largest and smallest scales get the idea that they understand the planetary scale? I'm sure the folks at the Hadley Centre, for instance, would be happy to entertain this interesting fellow and give him a more nuanced view.
So, why didn't he bother?
Update: A much better TED talk on geoengineering by David Keith. He seemed more optimistic than I thought was warranted, mostly based on the AGU session in 07, though.