Will the planet soon become uninhabitable for humans?

Six out of nine. It’s the sad number of Planetary boundaries that were surpassed, for the first time in 2015, Then in 2022. It was founded in 2009 by an international team of 26 researchers from scientific journals nature And ecology and society, The nine thresholds that should not be crossed on a global scale were intended to enable assessment The general effect of human activities on the planet. Fourteen years later, the conclusion is clear: if humanity continues down this path, the viability of the Earth by men and women can be called into question.

She is reading a file Promoter report I realized it’s not just a problem climatebut we have a global problem with planetary boundaries,” recalls Audrey Bohle, science journalist and author From the podcast and book of the same name last limits.

Published in 1972 by researchers at the Massachusetts Institute of Technology (MIT), led by Dennis Meadows, growth limits It is the bed book for many researchers. And for good reason: it models different scenarios in which, depending on the trajectories of greenhouse gas emissions and consumption uses, they can make sense of the potential worlds of tomorrow. More or less enviable depending on the path chosen.

Possible system crash

Population, industrial and agricultural production, pollution, the state of non-renewable resources … The boundaries of the planet are manifold and they affect all sectors of development of the thermo-industrial civilization. What is clear is that if we continue to grow, we will reach the collapse of the system [d’ici 2100]. Either because we will be inundated with pollution, including carbon dioxide. Either because we risk finding ourselves against a wall because of the use of Non-renewable sourceslike oil, which today guarantees the continuation of this growth, ”explains Audrey Bohle. In short, a real reckless rush.

But what, concretely, are the main issues related to transgression of planetary boundaries? What are the risks of going beyond the tipping points associated with these limits? Are its consequences reversible? On the occasion of Earth Day on April 22, with the aim of raising awareness of the impact of human activities on the climate, but also on soils, fresh water resourcesbiosphere and biochemistry cycles, 20 minutes He returns to the concept of planetary boundaries with journalist Audrey Boyle facing the camera.

Emily Small