‘Risk to human society’: Earth has exceeded critical planetary boundaries, says a study

Produced by: Tarun Mishra Designed by: Manoj Kumar

Global Environmental Systems Under Threat

A new study warns that human activity is endangering eight critical life-support systems on Earth, with seven already having crossed dangerous thresholds. The findings were published in the Lancet Planetary Health and involve more than 60 researchers assessing the state of the planet.

Planetary Boundaries and Ecosystem Health

Scientists examined various aspects essential for a liveable Earth, such as climate, freshwater systems, biodiversity, and soil nutrients. Most of these systems have crossed crucial “planetary boundaries,” indicating risks to both human society and the environment.

Aerosols as the Only System Within Limits

Among the systems evaluated, only aerosols—small particle pollution—remain within safe limits, despite contributing to an estimated 8 million deaths annually. This marks it as the last boundary yet to be breached, according to the study.

Origins of Planetary Boundary Research

The study updates a project that began in 2009 to assess these boundaries, now referred to as “Earth-system boundaries.” The research evaluates the risks of exceeding these thresholds on both the environment and society globally.

Two Key Measures of System Health

Researchers analysed these systems using two metrics: safety, which measures how long the systems can function reliably, and justice, which considers the potential harm to current and future generations. Both factors suggest critical changes are needed to avoid further damage.

Recommended Actions to Prevent Further Harm

The report recommends countries protect at least 50% of global ecosystems, limit groundwater extraction, and impose strict controls on nitrogen and phosphorus fertilizers. These steps are seen as necessary to stabilize Earth’s systems.

Economic Activity Driving Environmental Decline

According to the study, economic activities are a key driver of the planet’s destabilization. The authors propose “radical” societal changes, including wealth redistribution, to slow down environmental degradation and maintain a liveable planet.

Debates on Boundaries and Solutions

The “planetary boundaries” approach has sparked debate among scientists, with some questioning the practicality of the recommendations. Critics argue that the concept of crossing a defined danger line may oversimplify the complex environmental challenges the world faces.