A recent study conducted by the Earth Commission reveals that seven out of eight Earth System Boundaries (ESBs), crucial for the planet’s health and species survival, have been surpassed, raising concerns about the potential for a climate catastrophe. The findings were published in the journal Nature on May 31.
The assessment indicates that the transgression of ESBs is widespread, with more than half (52%) of the world’s land area and 86% of the global population already affected by the breach of two or more ESBs. According to experts’ map, South Asia (including India), Europe, and parts of Africa are hotspots for ESB transgressions, particularly in the Himalayan foothills where at least five ESB breaches have occurred.
For the first time, the Earth Commission established a set of ESBs at global and sub-global scales, encompassing climate, the biosphere, fresh water, nutrients, and air pollution. These boundaries were selected because they represent the major components of the Earth system and interconnected processes that support life and human well-being. They are also subject to threats from human activities and have the potential to affect global Earth system stability and development.
Among the breached ESBs are climate (including wet bulb temperatures above 35°C for at least one day per year and expansion of low-elevation coastal zones), functional integrity, and levels of surface water, groundwater, nitrogen, phosphorus, and aerosols. The remaining ESB, which has yet to be crossed, pertains to climate and includes the distinction between “safe” and “just” levels of warming. Currently, 1°C of warming exceeds the “safe and just” threshold, while 1.5°C of warming carries a higher likelihood of triggering tipping points and ecosystem damage. The study warns that beyond 1.5°C or 2°C warming, the risk of triggering tipping points and exacerbating climate feedbacks significantly increases.
The ESBs related to global warming aim to limit the probability of reaching climatic tipping points while preserving the functionality of the biosphere and cryosphere. The study emphasizes the urgent need for collective action to address these breaches and mitigate the potential consequences of climate change.