We have exhausted the Earth: seven of the nine planetary boundaries are in the red zone

Humanity has already crossed seven of the nine planetary boundaries that determine the Earth's stability, and all seven are in the worst condition ever recorded – according to the 2026 Planetary Health Check. The annual assessment was published on Monday by the Planetary Boundaries Science Lab at the Potsdam Institute for Climate Impact Research (PIK) in Germany; the report was prepared by more than sixty scientists.

“The diagnosis is clear. Pressure is increasing along every planetary boundary that already lies outside the safe operating space. (...) This means the risk of large-scale, persistent and potentially irreversible changes is growing, while our room for maneuver to manage them is shrinking.”

– said Boris Sakschewski, a PIK researcher and one of the report's lead authors.

The theory of planetary boundaries was developed in 2009 by Johan Rockström, PIK's current director, and his fellow researchers at the Stockholm Resilience Centre. The framework describes nine Earth system processes that must stay within safe limits for the planet to remain stable and resilient – that is, for conditions livable for human civilization to be maintained. According to the report, the boundaries that have been crossed are climate change, biosphere integrity (meaning biodiversity and ecosystem functioning), land-system change (mainly deforestation), freshwater use, disruption of biogeochemical cycles – primarily nitrogen and phosphorus – emissions of so-called novel entities such as plastics and synthetic chemicals, and ocean acidification. The latter is the most recent: it was the seventh boundary to be crossed, according to last year's report. Since the start of industrialization, the pH of the ocean's surface waters has dropped by about 0.1 units, representing roughly a 30 percent increase in acidity, driven mainly by fossil-fuel-derived carbon dioxide.

Only two boundaries remain within the safe zone: stratospheric ozone depletion and atmospheric aerosol loading. Both have improved over the past decade, but the authors warn that this global improvement may mask the fact that aerosol levels remain dangerous in certain regions. Levke Caesar, the lab's lead researcher, emphasized in an email to Courthouse News that these processes cannot be viewed in isolation.

“We are not pushing seven independent systems beyond their safe limits; we are altering several parts of one interconnected system at the same time.”

– she said. She added that climate change and biosphere integrity are considered the two “core boundaries,” not because the others are secondary, but because a lasting change in either of these two could, on its own, fundamentally alter the state of the Earth system.

The report follows a year marked by a series of weather disasters linked to human-caused warming. In 2025, monsoon floods in Pakistan affected more than 6.9 million people. Ocean heat content set a new record last year, contributing to Hurricane Melissa's extremely rapid intensification into a Category 5 storm before it reached Jamaica. Between January 2023 and September 2025, about 84.4 percent of the world's coral reefs were exposed to heat stress severe enough to cause bleaching – the largest such event ever recorded. This year, Western Europe experienced its warmest June–July period since records began. Drought struck France, Spain, Germany and the United Kingdom, massive wildfires ravaged parts of Europe and Canada, and record heat was recorded in Japan, South Korea and parts of the Middle East. According to Scientific American, atmospheric carbon dioxide concentration rose to a record 426 parts per million (ppm). This is well above the 350 ppm level many scientists consider safe, and far above the pre-industrial level of 280 ppm.

One of the most troubling questions raised by the report is whether terrestrial carbon sinks – forests and soils that absorb a significant share of human carbon dioxide emissions – are weakening under repeated heat, drought and fires. According to the authors, models estimating the capacity of these carbon sinks may overestimate how resilient these systems actually are.

“Our path to net zero relies on functioning carbon sinks. Current observations are alarming signs that our planet may be losing its buffering capacity.”

– said Sakschewski. Johan Rockström struck a tone that was both urgent and hopeful.

“We don't have the luxury of delay, but we do have the knowledge, the ability and the solutions to change course.”

– he said. According to him, protecting people's lives and livelihoods requires accelerating efforts to bring every planetary boundary back within the safe operating space. Hindou Oumarou Ibrahim, chair of the Planetary Guardians group that supports the report, asked readers to reread the list of disasters once more:

“Pakistan, the Caribbean, Europe, coral reefs in the depths of the oceans. These are not isolated emergencies. The planet is signaling, in every region at once, that its balance has been thrown off.”

The Planetary Health Check has been published annually since 2024. The first edition identified six crossed boundaries, and last year's report already showed seven. The framework also has its critics: some development researchers argue that its application could place disproportionate burdens on the Global South.

Source: PIK-Potsdam, Courthouse News

Ugar