earth system boundaries

Biosphere “Our Biosphere includes people and all other living organisms that we directly or indirectly interact with. The Biosphere is our common heritage that sustains human existence.”
Climate “We find that global warming beyond 1.0 °C above pre-industrial levels, which has already been exceeded, carries a moderate likelihood of triggering tipping elements.”
The authors have provided a bit of a summary of their proposals at The Conversation.
The Problem – “Past performance is not a guarantee of future results.”