Tag: #GeoengineeringGovernance

#145 The Earth: The Thermostat Changes Hands

If you measure this planet not by its age but by the time it has left for complex life, it stands late rather than in the middle. It is roughly four and a half billion years old, and the window for multicellular life closes in about eight hundred million to one billion years. The reason is the sun. It grows about ten percent brighter every billion years, silicate rock weathering therefore pulls ever more CO2 out of the air, and at some point the concentration falls below the threshold at which plants can still perform photosynthesis. Oxygen follows, probably within a geologically short span. Around eighty percent of the time in which this Earth could carry anything like us is already behind us.