At Cato Unbound, Jim Manzi argues for low-cost solutions to climate change. Joseph Romm makes the case that we are headed for catastrophe if we do not do anything.
My sense is that over the past year, the debate has changed in subtle ways, as evidenced by the Cato Unbound essays (which I recommend reading). On the Right, there has been an emphasis on the high cost of altering energy usage, in comparison with adaptation or trying to use technology to reduce atmospheric carbon dioxide. On the Left, they are ratcheting up their forecasts of doom--predicting greater temperature increases, higher sea levels, and so on.
Romm cites a study suggesting that carbon reduction might not involve any economic cost.
a 20% reduction in global emissions might be possible in a quarter century with net economic benefits.
I have difficulty reconciling Romm's forecast of a huge rise in atmospheric carbon concentrations with his optimistic view of alternative energy technology. If atmospheric carbon concentration shoots up, I assume it will be because we have tapped into high-marginal-cost fossil fuels, such as shale oil. I don't see why the market would do that if alternative energy is going to be cheaper.
Why do global warming alarmists want government to interfere with energy markets? It seems to me that they have to believe either
(a) that Romm is wrong about the free lunch in alternative energy. We will have to pay a stiff price to reduce atmospheric carbon dioxide, and the free market won't want to pay it;
(b) markets are perverse; even though alternative energy will be cheaper at the margin, the market will choose fossil fuels instead;
(c) markets are intrinsically bad; our lifestyles are intrinsically bad; government should be in of control energy production and consumption
I think that (a) is probably true, at least for the next twenty years or so. I think that (b) is unlikely to be true. I worry that (c) is the core belief from which the fear of global warming follows, rather than the other way around.