Introduction

The article discusses the updated planetary boundaries framework, which identifies nine critical processes responsible for maintaining Earth’s stability. The framework finds that six of the nine boundaries have been breached due to human activity, highlighting that Earth is outside the safe operating space for humanity.

Biosphere integrity

The planetary functioning of the biosphere is critical to regulating Earth’s state. Human activities, such as deforestation and degradation of soil and water, significantly reduce Earth’s functional biosphere integrity. The report proposes controlling human appropriation of net primary production to ensure the maintenance of functional biosphere integrity.

Land-system change

Human activities, such as urbanization, agriculture, and forestry, are responsible for increased soil erosion and nutrient depletion. This boundary is currently being breached, and it significantly affects the global carbon cycle, water and nutrient cycles, and biodiversity in natural ecosystems.

Freshwater use

Increased demand for freshwater resources has significantly affected the availability and quality of water resources. This boundary has been breached on a global level, affecting water-dependent ecosystems, wetlands, and aquatic biodiversity.

Biogeochemical flows

Human activities, including the use of nitrogen and phosphorus in agricultural practices and industrial pollution, result in significant increases in nitrogen and phosphorus flows from land to water bodies. This boundary is presently breached at the global level, significantly impacting freshwater ecosystems and oceanic biodiversity.

Ocean acidification

Human activities have resulted in significant increases of carbon dioxide emissions, affecting the ocean’s acidity levels and marine life. This boundary is close to being breached, with dire consequences for marine ecosystems and the seafood industry.

Atmospheric aerosol loading

Human activities, including industrial processes and transportation, affect atmospheric aerosol loading levels globally, leading to significant environmental and human health impacts. This boundary has already been breached in some regions globally.

Climate change

Human activities, including burning of fossil fuels, deforestation and agriculture, have significantly contributed to climate change. Emissions have already affected the climate system, with global temperatures already above pre-industrial levels. The report underscores the need to consider climate change and other anthropogenic impacts on the Earth system in a systemic context.

Stratospheric ozone depletion

Human activity, including the use of CFCs, has contributed to significant stratospheric ozone depletion, already affecting human health, agriculture, and ecosystems. While the report suggests slight recovery in this area, it is crucial to continue monitoring to avoid further depletion.

Novel entities

Human-made novel entities, including micro and macro waste and chemicals, have increased significantly, affecting the Earth system and human health. The report highlights the need to identify, monitor and control their impacts on human and ecosystem health.

Recommendations

The report highlights the need to maintain functional biosphere integrity, which requires controlling human appropriation of net primary production. Land-system change boundary must also be respected, given its critical role in controlling climate change. In addition, the report suggests more Earth system models that capture geosphere-biosphere-anthroposphere interactions to better understand and manage risks to Planet Earth.