Despite the common assumption that Earth always will and always has been able to support human life, we live on planet with a dying biosphere that only will soon end this current brief period of naturally support for complex life.

Our rare, if not unique, opportunity is to use the window rather than prematurely close it.

Assuming climate change is an existential threat and not merely an inconvenience, but CO2 emissions are only 1 of 9 planetary boundaries that must be observed in the to keep the window open.

The dawn of the Anthropocene puts risks not only long-term CO₂ balance, but the challenge of working within all planetary boundaries and respect that, growth within a shrinking biosphere will from now be a restraint for the rest of the our age of one finite planet, and until we can seize the opportunity to become multi planet to this one currently dying planet and before it’s too late.