Am not sure how familiar you are with work of eminent Climate scientist James Lovelock FRS . Ten years ago he predicted it was already too late to avoid collapse in human civilization. I thought it might be of interest to you Youtube James Lovelock, end of civilization.

Eoin Treacy's view

Thank you for this email and I believe this video is what you are referring to. It makes for sobering viewing. The primary point is when a system experiences aberrations a positive feedback loop begins which exaggerates future movements. 

Geoffrey West’s book Scale makes much the same point. His point is the heat build-up in a closed system is finite and will ultimately result in a significant upset. Both could be considered paradigm shifts in that it would be a virtually instant change in the environment. That is also implied in the desire to contain temperature rises to 1.5%. The assumption is a warming beyond that level would be catastrophic.

I am very much of the view that trying to completely reorient the entire global economy in new and exciting ways in an unproven manner is very risky and not guaranteed to provides the solution desired.