The point is, the answers to these questions really matter.

The scientists are largely guessing, and their guesses vary widely, though some guesses have much more going for them than others. What seems to be happening is that some of the most powerful people on the planet - especially those in power in the USA, which is the one that really matters - are using those differences as a reason for putting it all on the back burner.

Finding out the answers as to which are the most probably scenarios, and what can be done to minimise disastrous results is desperately important.

The parallels with what happened with the tobacco companies for decades is frightening - "Scientists aren't all agreed, so we should carry on encouraging people to smoke until it's been proved it kills, and we shouldn't go frightening them about things that may never happen." And you can always find some scientist to argue any case, it seems, the same way you can find a lawyer. The difference being that lawyers have a duty to do that, whereas the duty of scientists should lie elsewhere.