Only the acidity of the oceans, the health of the air and the ozone layer are within the boundaries considered safe, and both ocean and air pollution are heading in the wrong direction, the study said.

The framework is based on the science of the Earth system and identifies nine processes critical to maintaining its stability and resilience, and only ocean acidity, air health and the ozone layer are within limits considered safe.

Meanwhile, ocean pollution, like atmospheric pollution, is heading in the wrong direction, the paper read.

But ocean acidification is on the verge of being breached and aerosol loading is regionally above the cap, while stratospheric ozone levels have recovered slightly, the report added.

“We are in very bad shape,” said study co-author Johan Rockstrom, director of the Potsdam Institute for Climate Impact Research in Germany. “We show in this analysis that the planet is losing resilience and the patient is sick.”

In 2009, Rockstrom and other researchers created nine different broad boundary areas and used scientific measurements to judge Earth’s health as a whole.

Water went from barely safe to the out-of-bounds category because of worsening river run-off and better measurements and understanding of the problem, Rockstrom said.

These boundaries “determine the fate of the planet,” said Rockstrom, a climate scientist. The nine factors have been “scientifically well established” by numerous outside studies, he said.

If Earth can manage these nine factors, Earth could be relatively safe. But it’s not, he said.

The simulations showed “that one of the most powerful means that humanity has at its disposal to combat climate change” is cleaning up its land and saving forests, the study said. Returning forests to late 20th-century levels would provide substantial natural sinks to store carbon dioxide instead of the air, where it traps heat, the study said.

Biodiversity – the amount and different types of species of life – is in some of the most troubling shape, and it doesn’t get as much attention as other issues, like climate change, Rockstrom said.

The fact that the ozone layer is the sole improving factor shows that when the world and its leaders decide to recognise and act on a problem, it can be fixed and “for the most part, there are things that we know how to do” to improve the remaining problems, said Carnegie Mellon chemistry and environment professor Neil Donahue.

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