Six of the planet's nine frontiers, including climate change, deforestation, biodiversity loss, synthetic chemicals, freshwater depletion and nitrogen use, are now at alarmingly high levels, according to an international team of 29 scientists.
A devastated forest area in Brazil. Photo: Reuters
Two of the remaining three, ocean acidification, and atmospheric particulate and dust pollution, are now borderline. Only ozone depletion is currently within safe limits.
Planetary boundaries define “the key processes that have kept Earth as favorable for the development of life as it has been for the past 10,000 years,” said Katherine Richardson, a professor at the University of Copenhagen.
Research on the boundaries was first published in 2009. At that time, only climate change, biodiversity loss and nitrogen use were considered to have exceeded their limits.
“There is no sign that any of the boundaries, except the ozone layer, are recovering since the chemicals that destroy it were banned,” said co-author Johan Rockstrom, director of the Potsdam Institute for Climate Impact Research (PIK). “This means that we are losing resilience, that we are putting the stability of the Earth system at risk.”
A key finding of the report is that different boundaries amplify each other.
The study specifically looks at the interaction between rising CO2 concentrations and damage to the biosphere, particularly deforestation and rising temperatures when one or both increase.
It shows that even if humanity rapidly reduces greenhouse gas emissions, unless the destruction of carbon-absorbing forests is stopped, global warming will not stop.
“Along with climate change, the integrity of the biosphere is the second pillar for our planet,” said co-author Wolfgang Lucht, head of Earth System Analysis at PIK. “We are currently destabilizing this pillar by removing too much biomass, destroying too many habitats, and destroying too many forests.”
The study also concluded that all boundaries can be brought back into safe operating space if approached correctly.
Hoang Nam (according to AFP)
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