The Planetary Boundaries Science (PBScience), a new initiative led by the Potsdam Institute for Climate Impact Research (PIK) and supported by the Planetary Guardians and other partners, has launched its inaugural Planetary Health Check Report (September 2024). The initiative aims to track and annually report on the health of the Earth using the Planetary Boundaries framework, in order to help decision-making by governments, companies, international organisations and all citizens.
Human Level’s Take: Two-thirds of our nine Planetary Boundaries have been breached. One more is on the verge of transgression. Only two Planetary Boundaries remain in the safe zone. We are reaching an indisputable crisis point for the health of the Earth, which means it’s a crisis point for all life on Earth. And unchecked industrialisation without mitigating measures—business as usual—means we are only going to continue to move into the red. The Planetary Boundaries Science initiative makes startlingly clear that monumental systems change is needed to tackle the scale of the interconnected impacts that human activity has on the planet. Governments, businesses, investors and international organisations will need to be the drivers for cross-collaboration at serious scale—we cannot address one Boundary without addressing all nine. The moment calls for strong and immediate action by the actors that can push the change, because our lives literally depend on it.
Key points from the report:
- Nine Planetary Boundaries preserve stability and support life on Earth: The Planetary Boundaries (PBs) framework monitors nine processes and systems that are proven to regulate Earth’s health—preserving stability and support for life. They are interconnected, meaning that adequately addressing one requires action on all nine. The nine PB processes are: (1) Stratospheric Ozone Depletion, (2) Increasing Atmospheric Aerosol Loading, (3) Ocean Acidification, (4) Freshwater Change (both blue water—found in lakes, rivers, glaciers, etc.; and green water—water in the soil and plants), (5) Land System Change, (6) Climate Change (CO2 concentration and radiative forcing), (7) Modification of Biogeochemical Flows (both nitrogen and phosphorus cycles), (8) Introduction of Novel Entities, and (9) Change in Biosphere Integrity (both functional integrity and genetic diversity). These processes are rated in three categories: Safe Operating Space, Increasing Risk and High-Risk Zone.
- Six Boundaries breached: Six out of the nine Planetary Boundaries have gone past safe levels, and a seventh, Ocean Acidification, is approaching the High-Risk Zone. some text
- (1) Climate Change: CO2 levels are at a “15-million-year-high” and global mean temperatures are higher now than at any point since the emergence of human life.
- (2) Change in Biosphere Integrity: We are losing both genetic diversity of species and functional integrity (measured as the energy available to ecosystems). This is an indicator that our biosphere may be losing its resilience and adaptability. This can mean diminishing capacity of the Earth to mitigate other pressures, like the transgression of other PBs.
- (3) Land System Change: Global and regional forests are declining across every major forest biome due to deforestation. Most regions already sit in the High-Risk Zones, and others are joining (including temperate and tropical America).
- (4) Freshwater Change: Water flow and soil moisture are increasingly variable and unstable. This can mean impacts to the availability of clean water and environmental stability.
- (5) Modification of Biogeochemical Flows: Phosphorus and nitrogen use in agriculture has exceeded safe boundaries, leading to water pollution, eutrophication, algal blooms and “dead zones” in both freshwater and marine ecosystems. This issue already exists for industrialised countries but is now becoming a concern in developing countries too.
- (6) Introduction of Novel Entities: These include synthetic chemicals, plastics and genetically modified organisms—all of which can disrupt Earth system processes, harm ecosystems and lead to “possibly irreversible” impacts to the environment. The report says that the full environmental impacts for many entities is not yet known, which suggests that the PB has likely been exceeded.
- We need to avoid crossing tipping points: Tipping points happen when natural self-reinforcing feedback processes (like a rainforest keeping itself moist) are disrupted causing a system to change state (like a rainforest transitioning to self-drying and becoming a savanna). Human activities can drive systems past tipping points, causing their response to become nonlinear and disproportionately sensitive to small changes. Tipping points are different from PBs: where PBs are safe ranges for health indicators, tipping points are the moment when we cross those thresholds (the report explains it as equivalent to measuring blood pressure—the PB—to assess the risk of a heart attack—the tipping point). The report identifies eleven systems at risk of reaching tipping points: Freshwater Ecosystems and Environments; Coastal Ecosystems and Environments; Marine Ecosystems and Environments; Forests; Savannas, Grasslands and Drylands; Monsoon; Ocean Overturning Circulation; Permafrost; Ice Sheets; Glaciers; and Sea Ice.
