World Crosses Critical Planetary Boundaries: Study Reveals Alarming Trends

Context:

A recent study published in the journal Science Advances reveals that the world has exceeded six out of the nine planetary boundaries crucial for preserving Earth’s stability and resilience.

Relevance:

GS III: Environment and Ecology

Dimensions of the Article:

1. Planetary Boundaries
2. Key Highlights of the Study: Breached Planetary Boundaries
3. Way Forward to Address Planetary Boundary Challenges

Planetary Boundaries

• Proposed in 2009 by Johan Rockström and 28 eminent scientists.
• A framework to establish safe environmental limits for human activity.

Nine Crucial Planetary Boundaries

• Climate Change
• Biosphere Integrity: Involves biodiversity loss and species extinction.
• Stratospheric Ozone Depletion
• Ocean Acidification
• Biogeochemical Flows: Concerning phosphorus and nitrogen cycles.
• Land-System Change: Includes issues like deforestation.
• Freshwater Use: Encompasses alterations in the land water cycle.
• Atmospheric Aerosol Loading: Refers to microscopic atmospheric particles impacting climate and living organisms.
• Introduction of Novel Entities: Covers substances like microplastics, endocrine disruptors, and organic pollutants.

Consequences of Boundary Breach

• Breaching these boundaries doesn’t signify immediate catastrophe.
• However, it escalates the risk of irreversible environmental changes.
• This, in turn, threatens the Earth’s ability to sustain our current way of life.

Key Highlights of the Study: Breached Planetary Boundaries

• Climate Change:
  • Safe Boundary: Atmospheric CO2 concentration and radiative forcing set at 350 ppm and 1 Wm−2.
  • Current Status: 417 ppm and 2.91 W m−2.
• Biosphere Integrity:
  • Safe Boundary: Less than 10 extinctions per million species-years.
  • Current Extinction Rate: Estimated greater than 100 extinctions per million species-years.
  • Threatened Species: Approximately 1 million out of 8 million species are at risk.
  • Genetic Diversity Loss: Over 10% of plant and animal genetic diversity lost in the last 150 years.
• Land System Change:
  • Safe Boundary: Forested land area > 75%.
  • Current Status: Global forested land area at 60%.
• Freshwater Change:
  • Safe Boundaries:
    • Blue Water: 10.2%
    • Green Water: 11.1%.
  • Current Status:
    • Blue Water: 18.2%
    • Green Water: 15.8%.
• Biogeochemical Flows:
  • Safe Boundaries:
    • Phosphorus: 11 Tg.
    • Nitrogen: 62 Tg.
  • Current Status:
    • Phosphorus: 22.6 Tg.
    • Nitrogen: 190 Tg.
• Novel Entities:
  • Safe Boundary: Zero.
  • Current Status: Human impact on novel entities (e.g., microplastics, endocrine disruptors, organic pollutants) has exceeded the zero boundary.
• Safe Boundaries:
• Stratospheric ozone depletion, aerosol loading, and ocean acidification remain within the planetary boundaries.

Way Forward to Address Planetary Boundary Challenges:

• Biodiversity Conservation:
  • Implement conservation programs aimed at preserving biodiversity, restoring ecosystems, and protecting endangered species and genetic diversity.
• Circular Economy:
  • Embrace circularity principles to promote resource regeneration, minimize waste, and ensure the continual repurposing of valuable materials instead of discarding them.
• Waste Management and Pollution Control:
  • Enforce strict regulations on waste disposal, encouraging recycling and reducing pollution from novel entities like microplastics.
• Community Empowerment:
  • Empower communities to actively engage in sustainable practices, fostering a collective sense of responsibility for environmental stewardship.
• Climate Mitigation:
  • Prioritize climate mitigation strategies to limit temperature rise and prevent further breaches of planetary boundaries related to climate change.
• Clean Technologies and Sustainable Transportation:
  • Promote zero-emission technologies and reduce carbon footprints through incentives for clean energy adoption and the adoption of sustainable transportation methods.

-Source: Down To Earth