If we bring social justice into the global-boundaries discussion, we suddenly realise we have a lot less wiggling room than we initially thought. In fact, we don’t have much wiggling room at all if we hope to stop globally crucial ecosystems and species from spiralling into chaos—and potentially dragging humanity down with them.

This is significant research conducted by a team of 51 researchers from around the world. It attempts to provide an integrated examination of the boundaries of eight of the world’s ecological systems (covering climate, the biosphere, water, the nutrient cycle, and aerosols), and therefore gives a picture of our planet’s sustainability far beyond merely looking at climate change. Moreover, the study focuses not only on the technical (or safe) limits, but also it estimates boundaries which are just.

For example, we are still, but only marginally, within the safe boundary for climate change (+1.5°C), whereas the just limit is exceeded regularly because even at +1°C many millions of poorer people have suffered from climate-change induced heatwave conditions, often in countries that make little contribution to climate change. Aerosols are an example where both the safe boundary and the just boundary have been exceeded, and it is clear that there is no easy way back. About "85% of the world’s population is currently exposed" at the just boundary levels, and exposure to ambient particulates “is estimated to cause 4.2 million deaths annually”.

The conclusion to the paper suggests that there must be a systemic global transformation in energy, food, urban and other sectors, that addresses economic, technical and political change, ensuring access for the poor by reducing resource use and redistribution.

This is an important reminder of our reliance on the biosphere. Taking stock of the bigger picture of the health of the biosphere is crucial for avoiding significant harm. 

As the authors outline, maintaining intact ecosystems is necessary for the Earth system functions that all species – including humans – depend. 

Currently there appears to be a lack of regard for the importance of intact ecosystems in many parts of Australia, with ongoing loss of species habitat to make way for development. Intact ecosystems maintain hydrological flows that are crucial in a water-limited continent such as Australia. Intact ecosystems are important for preventing erosion and salinisation, maintaining soil health, climate regulation, avoiding runoff entering fragile freshwater rivers and creeks and polluting the Great Barrier Reef. Intact ecosystems also sequester and store carbon. 

Studies have shown that between 60 and 80 percent of the original extent of our natural ecosystems need to be maintained to deliver these crucial services. Restoration is extremely labour-intensive and expensive, and can take decades to function as an intact ecosystem. The most cost-effective method is to prevent the loss and degradation of ecosystems in the first place.

Global environmental degradation has already worsened global social inequities. The hotspot map shows where suffering may trigger new civil unrest.