Earth Commission · Global Commons Alliance · Future Earth

Earth System Boundaries

The stability of the Earth system and human well-being are inseparably linked, yet their interdependencies have long been treated separately. The Planetary Boundaries framework identified the biophysical thresholds that keep the planet in a stable, Holocene-like state — but remaining within those limits does not, on its own, guarantee justice. Biophysical boundaries are not inherently just: strict environmental limits, such as reducing emissions or setting aside land for nature, can reduce access to food, water, energy and land for vulnerable people. The Earth Commission, an independent scientific body hosted by Future Earth and the Global Commons Alliance, set out to address this gap through a multi-year collaboration between natural and social scientists from the Global North and South.

Earth system justice

At the heart of this work is the concept of Earth system justice — an integrated framework that reduces the risks of global environmental change (safe) while ensuring well-being and an equitable sharing of nature’s benefits, risks and responsibilities among all people (just), within Earth system boundaries that provide universal life support.

The framework rests on three overarching justice dimensions, called the “3 Is”:

• Interspecies justice and Earth system stability — rejecting human exceptionalism, recognising that humans are guardians of the natural world, and preventing significant harm to other species and ecosystems.
• Intergenerational justice — addressing obligations between past and present generations (have past emissions already caused significant harm?) and between present and future generations (are we minimising the harm we leave behind?).
• Intragenerational justice — ensuring fairness between countries, communities and individuals alive today, viewed through an intersectional lens that considers how gender, race, age, class and health compound vulnerability and exposure.

Earth system justice also distinguishes between procedural justice (fair access to information, decision-making, civic space and courts) and substantive justice (access to minimum resources and services, reduction of harm, and equitable allocation of remaining resources, risks and responsibilities). These dimensions guide the identification of both just ends — boundaries and access levels that reduce significant harm — and just means — the transformations in governance, technology, consumption and economic systems needed to achieve them.

Safe and just Earth system boundaries

The Commission quantified eight safe and just Earth system boundaries across five domains: climate, the biosphere (natural ecosystem area and functional integrity), freshwater (surface water and groundwater), nutrient cycles (nitrogen and phosphorus), and aerosols and air pollution. For each domain, safe boundaries are set to maintain Earth system resilience and avoid triggering tipping points, while just boundaries are set to minimise significant harm — defined as widespread, severe, existential or irreversible negative impacts on people, communities, countries and the more-than-human world.

A crucial finding is that justice considerations often make boundaries more stringent than safety alone. For climate, for example, the safe boundary of 1.5 °C still exposes tens of millions of already vulnerable people to unprecedented heat; the just boundary is set at 1.0 °C. For aerosols and air pollution, local health standards impose limits well below the safe regional boundary. In two cases — climate and aerosols — the just boundaries are tighter than the safe ones, meaning that even a “safe” Earth system is not necessarily a just one.

Seven of the eight globally defined safe and just boundaries have already been transgressed. At the local level, in more than half of the world’s land area, at least two boundaries have been crossed — affecting 86 % of the global population. This reality underscores the urgency of systemic transformation.

The safe and just corridor

The space between the floor of minimum access for all people and the ceiling of Earth system boundaries defines what the Commission calls the safe and just corridor. The floor represents the level of resources — water, food, energy and infrastructure — needed for all people to live with basic dignity and escape poverty. The ceiling is the more stringent of the safe and just boundaries for each domain. If the floor exceeds the ceiling (when providing minimum access would itself push the system beyond its boundaries), the corridor does not yet exist and can only be created through profound redistribution, technological transformation and systemic change. Meeting the minimum needs of billions who currently lack adequate access to food, water, energy and infrastructure will increase pressure on the Earth system — making redistribution from the wealthiest consumers not optional, but necessary.

Our contribution

Our large-format visualisations supported the presentation by Johan Rockström and Joyeeta Gupta at the World Economic Forum 2023, effectively conveying the significance of recognising and addressing, for the first time, both biophysical boundaries (safe) and human well-being and justice (just).

References

Gupta, J., Liverman, D., Prodani, K. et al. Earth system justice needed to identify and live within Earth system boundaries. Nature Sustainability 6, 630–638 (2023). https://doi.org/10.1038/s41893-023-01064-1

Rockström, J., Gupta, J., Qin, D. et al. Safe and just Earth system boundaries. Nature 619, 102–111 (2023). https://doi.org/10.1038/s41586-023-06083-8

Gupta, J., Bai, X., Liverman, D.M. et al. A just world on a safe planet: a Lancet Planetary Health–Earth Commission report on Earth-system boundaries, translations, and transformations. The Lancet Planetary Health 8, e1134–e1177 (2024). https://doi.org/10.1016/S2542-5196(24)00042-1

Rockström, J. et al. A safe operating space for humanity. Nature 461, 472–475 (2009). https://doi.org/10.1038/461472a

Rammelt, C.F. et al. Impacts of meeting minimum access on critical earth systems amidst the Great Inequality. Nature Sustainability 6, 212–221 (2022). https://doi.org/10.1038/s41893-022-00995-5