The argument for large and expensive efforts to prevent or reduce global warming has three parts, in principle separable: Global temperature is trending up, the reason is human activity, and the consequences of the trend continuing are very bad. Almost all arguments, pro and con, focus on the first two. The third, although necessary to support the conclusion, is for the most part ignored by both sides…
The answer, I think, is that nobody knows if the net effects would be good or bad, and probably nobody can know. We are talking, after all, about effects across the world over a century. How accurately could somebody in 1900 have predicted what would matter to human life in 2000? What reason do we have to think we can do better?…
If we have no good reason to believe that humans will be substantially worse off after global warming than before, we have no good reason to believe that it is worth bearing sizable costs to prevent global warming. (leggi tutto)
lunedì 12 settembre 2011
Ragionamenti lasciati a metà: l’ effetto serra
Il prototipo è quello sul global warming: