From UPSC perspective, the following things are important :
Prelims level : Planetary Boundaries
Mains level : NA
- A recent study has delivered a stark message: humanity has breached six of the nine planetary boundaries that are crucial for maintaining Earth’s stability and resilience.
What are the 9 Planetary Boundaries?
- These boundaries encompass climate change, biosphere integrity, land system change, freshwater change, biogeochemical flows, and novel entities.
- These findings underscore the urgent need for a thorough reassessment of our environmental impact and the imperative of global collaboration to address these critical challenges.
Understanding Planetary Boundaries
(1) Setting Safe Limits:
- Planetary boundaries can be likened to the vital parameters in human health, such as blood pressure.
- Just as high blood pressure elevates the risk of heart disease, exceeding planetary boundaries heightens the risk of triggering irreversible environmental changes.
(2) An Evolving Framework:
- The planetary boundaries framework was introduced in 2009 to define the safe environmental limits within which humanity should operate.
- To remain relevant, the framework must adapt as our understanding of Earth’s complex systems and human impacts evolves.
The Third Iteration: Assessing Environmental Risks
(1) Identifying Critical Processes:
- Researchers examined processes within Earth’s ecosystem that have been vital for sustaining favourable conditions for humans over the past 12,000 years.
- This era is noted for its stable and temperate planetary conditions.
(2) Evaluating Human Impact:
- The study assessed the extent to which human activities are modifying these crucial processes.
- Computer simulations were employed to determine the point at which human activities could trigger irreversible changes in Earth’s systems.
(3) Alarming Revelations:
- The study found that human activities had breached safe boundaries for climate change and land system change as early as 1988.
- The current trajectory poses a substantial risk of systemic disruption.
Boundaries Crossed and Their Consequences
(1) Atmospheric Carbon Dioxide Concentration:
- The safe limit was set at 350 ppm; it currently stands at 417 ppm.
- This has led to significant climate change.
(2) Land System Change:
- The safe limit aimed to maintain 75% of the original forest cover; the current estimate is at 60%.
- Such alterations have profound consequences for land systems.
(3) Biosphere Integrity:
- The safe limit was fewer than 10 extinctions per million species-years; the actual rate has exceeded 100.
- This poses a severe threat to millions of plant and animal species.
(4) Freshwater Change:
- Boundaries have been exceeded for both blue (surface and groundwater) and green (water available for plants) water resources.
- This has negative consequences for ecosystems.
(5) Biogeochemical Flows:
- Safe boundaries have been surpassed for phosphorus and nitrogen flows.
- This has alarming implications for biodiversity and water quality.
(6) Novel Entities:
- The planetary boundary for novel entities was set at zero, and this boundary has been transgressed.
- Risks include stratospheric ozone depletion, aerosol loading, and ocean acidification.
Way Forward: Urgent Global Collaboration
(1) Lessons from the Ozone Layer:
- Successful global negotiations, like the Montreal Protocol, managed to restore the ozone layer to safe levels after transgression.
- Emphasizes the importance of adhering to limits on environmental waste.
(2) Embracing a Circular Economy:
- A circular economy, mirroring nature’s own system, is essential.
- Transitioning towards a circular economy represents a crucial step in tackling these planetary challenges.
- The study’s findings serve as a stark reminder of humanity’s responsibility to safeguard Earth’s delicate equilibrium.
- Breaching planetary boundaries not only poses immediate risks but also imperils the long-term sustainability of our planet.
- Urgent global cooperation and a commitment to respecting environmental limits are essential to avert a potentially catastrophic future.