"At the heart of the debate about climate change is a simple scientific question: can a doubling of the concentration of a normally harmless, indeed moderately beneficial, gas, from 0.03% of the atmosphere to 0.06% of the atmosphere over the course of a century change the global climate sufficiently to require drastic and painful political action today? In the end, that’s what this is all about. Most scientists close enough to the topic say: possibly. Some say: definitely. Some say: highly unlikely. The ‘consensus’ answer is that the warming could be anything from mildly beneficial to dangerously harmful: that’s what the IPCC means when it quotes a range of plausible outcomes from 1.5 to 4 degrees of warming."
If only this was to be the discussion to be held in Paris at the end of the month, but it isn't. This discussion is not on the agenda at all. It is not allowed, which is why no meaningful conclusions can be found.