By Sarah George

Copyright edie

This is the stark warning from researchers at the Potsdam Institute for Climate Impact Research today (24 September).

The seven breached boundaries are climate change, land system change, freshwater use, biochemical flows, ocean acidification, biosphere integrity and biogeochemical flows.

Outcomes are worsening across all seven of these areas.

Ocean acidification is new to this list for 2025. The world’s oceans are now at least 30% more acidic than they were in pre-industrial times, the researchers found. The initial impacts have been recorded on small creatures including pteropods, which are an important food source for larger animals.

Researchers have also observed coral reef bleaching and changes to fish mating and migration patterns.

Oceanographer Dr Sylvia Earle said: “The Ocean is our planet’s life-support system.

“Today, acidification is a flashing red warning light on the dashboard of Earth’s stability. Ignore it, and we risk collapsing the very foundation of our living world.”

The rise in acidification has been primarily attributed to fossil fuel emissions, which have increased global temperatures. Temperatures in 2024 averaged 1.55C above pre-industrial levels, per the WMO.

The ocean has absorbed around 90% of the warming that has occurred in recent decades, according to NASA. But its ability to do so in the future is likely to deteriorate.

Paul Polman, former Unilever CEO and co-vice chair of the Planetary Guardians initiative, said: “Crossing the ocean boundary underlines the fragility of our global economy and the urgency of change.

“Business, governments and civil society cannot afford delay. Just as we have seen with the ozone layer, coordinated action works. We need to apply the same resolve to restoring planetary health and protecting the ocean.”

Ozone focus

Only two of the planetary boundaries assessed remain within safe limits – aerosol loading and ozone depletion.

But the ozone faces new threats from the deployment of large fleets of satellites, including those operated by Starlink.

Studies have shown a significant increase in aluminium in the atmosphere and a corresponding rise in aluminium oxide aerosols due to satellite re-entry. Researchers estimate that an increasing number of planned satellite fleets could lead to an additional 360 metric tonnes of aluminium oxide emissions.

A rallying cry before COP30

The report on planetary boundaries has been released as world leaders are meeting in New York for the UN’s annual General Assembly (UNGA).

This is the last major international UN meeting before the annual climate summit, COP30, begins in Brazil in November.

Attention at the summit has been squarely on US President Donald Trump, who this year ordered the federal government to withdraw from the Paris Agreement on climate change and cease supporting the UN Sustainable Development Goals (SDGs) agenda.

Trump used his platform at the UNGA to call coal “clean and beautiful” and describe global warming as “a hoax”.

He also falsely claimed that China would not have to hit emissions targets under the Paris Agreement, nor provide any international climate finance, until 2030.

The US federal government will not attend COP30. It already skipped the Bonn intersessional climate talks, which took place in June.

Nonetheless, Brazil’s President-Designate for the COP30 has said that the unwavering commitment of many states, cities and businesses to the Paris Agreement means that the US will continue to be strongly represented.

Click here for full details of edie’s plans for covering COP30.