This climate sensitivity thing. Lewis, Annan etc.
It reminds me of something and I just cannot remember where I first saw it.Can’t even remember which number it was about.
But the general argument went that if a scientific number gets estimated (any number, distance of the Moon, Plank’s Constant, whatever) and the original estimate is well off then you never really do find anyone leaping up and shouting “Eureka! That’s Wrong!”.
Instead, over time you get a series of “refinements” from different authors the effect of which is to walk that estimate back to something much closer to reality. The implication was definitely that “everyone” knew that the original was well off. But no one really wanted to say so. Thus rather than confronting the error it gets slowly revised.
Does seem to me as if that’s happening over sensitivity. Only an impression, but…..
As to what it means: it means that it’s all a much cheaper problem to deal with. The more time we have the cheaper any solution will be.
Firstly, if we don’t have to Act Now! then we can wait until the technologies actually mature before installing vast amounts of them. It really isn’t going to be that long, wouldn’t think more than a decade, before solar is truly price competitive (40% efficient multi-junction cells for example) at which point their installation won’t even be a cost of combatting climate change. It’ll just be a natural reaction to a relative price change. The same is true of other technologies (although I’m not sure if windmills will ever make it).
Secondly, it means that we can (or at least could) work with the capital cycle rather than against it. Rather than replacing coal plants right now, as the EU is insisting we do, we could run them until they fall apart. Replacing them with renewables at the end of their life is obviously cheaper than closing them down early.
One way of describing this is that we move into a Nordhaus world rather than a Stern one. Instead of a medium carbon tax now, Stern’s $80, we could have a low now (Nordhaus suggests $5) but with a committment to raise it strongly to say $250 in 2040, 2050. There’s very little of our energy infrastructure that won’t be replaced anyway before 2050, but this would allow us to get the most use out of what we’ve already built and paid for.
Not that I expect a change in the science to actually feed through into a change in the political activity, more’s the pity.