Seven of nine planetary boundaries breached at record levels, scientists report

A coalition of 60 scientists led by the Potsdam Institute for Climate Impact Research has found that seven of the nine planetary boundaries defining a safe operating space for humanity are now breached at their highest recorded levels. The annual assessment, published Monday at the start of Climate Week in New York, tracks guardrails including climate change, biosphere integrity, land and freshwater systems, biogeochemical flows, and novel entities such as pollution. Ocean acidification entered the danger zone for the first time last year. Only stratospheric ozone and atmospheric aerosol loading have improved.

Lead author Boris Sakschewski said pressure is rising across every boundary already outside the safe operating space, shrinking the margin for error. The report warns that forests and oceans, which have absorbed much of the carbon humans have emitted, are faltering — with the Amazon at risk of tipping into savannah.

Co-author Johan Rockström said humanity still has the knowledge and capacity to reverse course. The assessment follows a year of record heat, wildfires, and floods that scientists attribute to the destabilization of natural systems.