The Planetary Boundaries Framework: Status (“PB3.0”)

The planetary boundaries framework emerges from Earth system science and was developed to help guide the global community in its efforts to manage Anthroposphere interactions with the Earth’s bio-physical components. In the third iteration of the framework, PB3.0 (September 2023), six of the nine boundaries are found to be transgressed and anthropogenic pressure is increasing on all the boundaries earlier found to be exceeded. Metrics are, for the first time, proposed for all boundaries. Human Appropriation of Net Primary Production is proposed as the control variable for the function of the biosphere as photosynthesis represents the energy input supporting almost all life. The probability of achieving global climate goals is argued to be closely linked to the fate of global forests. Thus, the climate and biodiversity crises must be addressed together. Directions for the framework’s further development are discussed.