Scientists set the limits not to be exceeded to preserve the Earth and humanity

They are running under the banner of the Earth Commission. They are more than 40 scientists from different backgrounds. From different countries. Today, they invite us to take a fresh look at those known as planetary boundaries. Those that were introduced by the Meadows report 50 years ago. Which show us how far we can go in the exploitation of our Earth.

For the first time, the team presents numbers and a solid scientific basis to assess the state of health of our Earth. In terms of stability and resilience. This aspect is rather classic in the matter. But also in terms of human well-being and equity. Showing the close link that binds us to our planet. “We cannot have a biophysically safe planet without justice”says Joyeeta Gupta, co-chair of the Earth Commission.

Researchers’ work now defines safe and just boundaries of the Earth system for five critical areas — climate, biosphere, water, nutrients and air pollution — which play a key role in maintaining the life and stability of our planet. Safe boundaries—understand those that guarantee stable and resilient conditions with a healthy planet as a reference point in a Holocene-like system—that include insights from tipping point science. And fair limits which prevent humans from being exposed to significant damage. Of type, chronic diseases, famines, loss of income or even death.

A solid foundation on which to build a sustainable future

For example, researchers point out that in the field of climate, the fair limit has already been crossed. It was 1°C above pre-industrial normals. And current global warming has reached the 1.2°C mark. The safe limit, meanwhile, still holds. It is fixed at +1.5°C. The trouble is that the one that the researchers call a safe AND fair limit, and which is based on the more restrictive of the two, has therefore also indeed already been exceeded. Showing how taking into account the notion of equity tightens the limits of the Earth system. “However, justice is a necessity for humanity to live within planetary boundaries. It is not a political choice. Overwhelming evidence shows that a just and fair approach is essential to planetary stability”underlines Joyeeta Gupta.

Another example is that of water management. The safe and fair limit is set at 20% change in monthly surface water flow. The researchers note that it is exceeded on 34% of the surface of the globe. The limit of annual abstraction below groundwater recharge has been exceeded on 47% of the world’s surface!

“This assessment provides all stakeholders with scientific boundaries on which to build to ensure prosperous and equitable global development on a stable planet, a better future for both planet and people”, remarks Johan Rockström, also co-president of the Earth Commission. All that remains is to do… but to do it quickly. Because “Never has the management of the global commons been so urgent and important to take in hand”concludes Wendy Broadgate, the executive director of the Earth Commission.