Back in 2009 researchers published the first report on exceeding the boundaries of Earth’s “safe operating space.” In 2015, there was an update. They concluded that the Earth had crossed the line beyond safety on at least four of nine boundaries—climate change, land use, biodiversity, and nutrient flows. Now, the researchers have published an even more disturbing update assessing the planet’s health—Earth beyond six of nine planetary boundaries—in which they add fresh water and forests to the list.
Only three boundaries, stratospheric ozone levels, air pollution, and ocean acidification are still inside the safety zone, and those two latter areas are edging up to the boundary.
The researchers note:
Currently, anthropogenic perturbations of the global environment are primarily addressed as if they were separate issues, e.g., climate change, biodiversity loss, or pollution. This approach, however, ignores these perturbations’ nonlinear interactions and resulting aggregate effects on the overall state of Earth system. Planetary boundaries bring a scientific understanding of anthropogenic global environmental impacts into a framework that calls for considering the state of Earth system as a whole.
Six of the nine boundaries are transgressed. In addition, ocean acidification is approaching its planetary boundary. The green zone is the safe operating space (below the boundary). Yellow to red represents the zone of increasing risk. Purple indicates the high-risk zone where interglacial Earth system conditions are transgressed with high confidence. Values for control variables are normalized so that the origin represents mean Holocene conditions and the planetary boundary (lower end of zone of increasing risk, dotted circle) lies at the same radius for all boundaries (except for the wedges representing green and blue water, see main text). Wedge lengths are scaled logarithmically. The upper edges of the wedges for the novel entities and the genetic diversity component of the biosphere integrity boundaries are blurred either because the upper end of the zone of increasing risk has not yet been quantitatively defined (novel entities) or because the current value is known only with great uncertainty (loss of genetic diversity). Both, however, are well outside of the safe operating space. Transgression of these boundaries reflects unprecedented human disruption of Earth system but is associated with large scientific uncertainties.
Note: Click here for a larger, more readable copy of the graphic.
Chelsea Harvey at E&E News reports:
Crossing these individual boundaries doesn’t mean that the planet immediately falls off a cliff, said Katherine Richardson, a biological oceanographer at the University of Copenhagen and lead author of the new report.
“The world isn’t gonna end tomorrow,” she said. “But the risk that we’re starting up processes that we cannot stop — and will change the planet and its overall health, its overall environmental conditions, drastically and irreversibly — is becoming greater and greater as we cross these boundaries.”
Said Richardson: "The Planetary Boundaries science provides a 'guide for action' if we truly want to secure prosperity and equity for all on Earth, and this goes well beyond climate only, requiring novel Earth system modeling and analysis, and systematic efforts to protect, recover and rebuild planetary resilience. Hopefully, this new study will serve as a wake-up call for many and increase focus in the international community on the necessity of limiting our impacts on the planet in order to preserve and protect the Earth conditions that allow advanced human societies to flourish.”
Since the 1960s, and especially since the 1980s, we humans have been treated to countless wake-up calls. Yet all too many politicians remain determined to sedate us as they continue business as usual sprinkled with greenwashing.