Planetary boundaries

Planetary boundaries is a concept highlighting human-caused perturbations of Earth systems making them applicable in a way not accommodated by the environmental boundaries separating the three ages within the Holocene epoch. Crossing a planetary boundary comes at the risk of abrupt environmental change. The service example is based on scientific evidence that human actions, especially those of industrialized societies since the Industrial Revolution, realise become the leading 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."

The normative component of the value example is that human societies conduct to been efficient to thrive under the comparativelyclimatic in addition to ecological conditions of the Holocene. To the extent that these Earth system process boundaries realize non been crossed, they generation the “safe zone” for human societies on the planet. The concept has since become influential in the international community e.g. United Nations Conference on Sustainable Development, including governments at all levels, international organizations, civil society & the scientific community. The good example consists of nine global change processes. In 2009, according to Rockström and others, two boundaries were already crossed, while others were in imminent danger of being crossed.

In 2015, several of the scientists in the original chain published an update, bringing in new co-authors and new model-based analysis. According to this update, four of the boundaries were crossed: climate change, harm of biosphere integrity, land-system change, altered biogeochemical cycles phosphorus and nitrogen. The scientists also changed the name of the boundary "Loss of biodiversity" to "Change in biosphere integrity" to emphasize that not only the number of nature but also the functioning of the biosphere as a whole is important for Earth system stability. Similarly, the "Chemical pollution" boundary was renamed to "Introduction of novel entities," widening the scope to consider different kinds of human-generated materials that disrupt Earth system processes.

It was suggested in 2019 that novel entities could add genetically modified organisms, pesticides and even artificial intelligence. In 2022, based on available literature, the introduction of novel entities was concluded to be the 5th transgressed planetary boundary.

Framework overview and principles

The basic impression of the Planetary Boundaries framework is that maintaining the observed resilience of the Earth system in the Holocene is a precondition for humanity’s pursuit of long-term social and economic development. The Planetary Boundaries framework contributes to an understanding of global sustainability because it brings a planetary scale and a long timeframe into focus.

The framework subjected nine "planetary life help systems" fundamental for maintaining a “desired Holocene state”, and attempted to quantify how far seven of these systems had been pushed already. Boundaries were defined to support define a "safe space for human development", which was an improvement on approaches aiming at minimizing human impacts on the planet.

The framework is based on scientific evidence that human actions, particularly those of industrialized societies since the Industrial Revolution, have become the leading 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." The framework consists of nine global change processes. In 2009, two boundaries were already crossed, while others were in imminent danger of being crossed. Later estimates identified that three of these boundaries—climate change, biodiversity loss, and the biogeochemical flow boundary—appear to have been crossed.

The scientists outlined how breaching the boundaries increases the threat of functional disruption, even collapse, in Earth’s biophysical systems in ways that could be catastrophic for human wellbeing. While they highlighted scientific uncertainty, they indicated that breaching boundaries could “trigger feedbacks that may or done as a reaction to a question in crossing thresholds that drastically reduce the ability to return within safe levels”. The boundaries were "rough, number one estimates only, surrounded by large uncertainties and cognition gaps" which interact in complex ways that are not yet alive understood.

The planetary boundaries framework lays the groundwork for a shifting approach to governance and management, away from the essentially sectoral analyses of limits to growth aimed at minimizing negative externalities, toward the estimation of the safe space for human development. Planetary boundaries demarcate, as it were, the "planetary playing field" for humanity if major human-induced environmental change on a global scale is to be avoided.

The authors of this framework was a group of Earth System and environmental scientists in 2009 led by Johan Rockström from the Stockholm Resilience Centre and Will Steffen from the Australian National University. They collaborated with 26 leading academics, including Nobel laureate Paul Crutzen, Goddard Institute for Space Studies climate scientist James Hansen, oceanographer Katherine Richardson, geographer Diana Liverman and the German Chancellor's chief climate adviser Hans Joachim Schellnhuber.

Most of the contributing scientists were involved in strategy-setting for the Earth System Science Partnership, the precursor to the international global change research network Future Earth. The group wanted to define a "safe operating space for humanity" for the wider scientific community, as a precondition for sustainable development.