Planetary Boundaries

Planetary boundaries define the ecological limits for human activities to maintain the Earth system.

The planetary boundaries are a scientific framework that defines the environmental limits within which humanity can safely operate to preserve the stability and resilience of the Earth system that has enabled the development of human civilization. The concept was introduced in 2009 by a group of scientists from Earth system and environmental sciences led by Johan Rockström to address the growing impact of human activities on the planet since the Industrial Revolution.

The framework identifies nine critical biophysical processes that regulate the functioning of the Earth's life-support systems. These processes include climate change, biosphere integrity, loss of biodiversity, and species extinction, changes in land use systems, changes in freshwater availability, biogeochemical flows, ocean acidification, atmospheric aerosol loading, stratospheric ozone depletion, and novel materials such as synthetic chemicals and microplastics. For each of these processes, scientists have attempted to quantify a safe operating space—a threshold that should not be exceeded to avoid destabilizing the Earth system.

The planetary boundaries are based on the understanding that the relatively stable conditions of the Holocene, which lasted for about the last 11,700 years, were critical for the development of human societies. Exceeding these boundaries could push the Earth system into a new, less hospitable state, which could have unpredictable and potentially catastrophic consequences for the well-being of humanity. Therefore, it is crucial to consider and effectively monitor these boundaries in global environmental management. Scientific institutions continue to do valuable work to refine the quantification of the boundaries and improve the monitoring of the Earth system to provide actionable insights for policymakers and the public.