Planetary Boundaries

What are Planetary Boundaries, and how did they come about?

Planetary boundaries are a framework to describe limits to the impacts of human activities on the Earth system. Beyond these limits, the environment may not be able to self-regulate anymore. This would mean the Earth system would leave the period of stability of the Holocene, in which human society developed. The framework (J. Rockström et al., 2023; J. Rockström et al., 2009; J. Rockström, W. Steffen, 2009A) is based on scientific evidence that human actions, especially those of industrialised societies since the Industrial Revolution, have become the main driver of global environmental change. According to the framework, "transgressing one or more planetary boundaries may be deleterious or even catastrophic due to the risk of crossing thresholds that will trigger non-linear, abrupt environmental change within continental-scale to planetary-scale systems."(J. Rockström et al., 2023) 

The Earth's system consists of the interactions and 'feedbacks', through material and energy fluxes between the Earth's subsystems' cycles, processes, and "spheres," which include the atmosphere, hydrosphere, cryosphere, geosphere and pedosphere (the ground layer of Earth), lithosphere, and biosphere. (Cockell, 2008)

What have we learnt about Planetary boundaries and their limits for human activity?

For the first time, humanity can now report on the state of nearly all of the boundaries. Here is how the graphical reporting of planetary boundaries has occurred in the last 20 years:

For further information, please go to the Stockholm Resilience Centre at Stockholm University

Wikipedia has more detail and a summary table.
 https://www.stockholmresilience.org/  accessed on 28/05/2024
 https://en.wikipedia.org/wiki/Planetary_boundaries accessed on 28/05/2024