We often worry about climate change and pollution, but scientists have uncovered an even more alarming deadline—Earth’s oxygen will eventually disappear. According to new research, our planet’s breathable atmosphere could vanish in about one billion years, much sooner than previously thought.
A team from Toho University and Georgia Tech ran complex simulations of Earth’s climate and biochemical processes, tweaking variables across hundreds of thousands of scenarios. Their findings, published in Nature Geoscience, suggest that oxygen levels will plummet rapidly in roughly a billion years, reverting our atmosphere to a state similar to before the Great Oxidation Event 2.5 billion years ago.
Lead researcher Kazumi Ozaki explained that while earlier estimates gave Earth’s biosphere two billion years before collapsing from overheating and carbon dioxide scarcity, oxygen depletion may actually happen twice as fast. Once it begins, the atmosphere will become methane-rich, with no ozone layer—making it uninhabitable for humans and most complex life.
The study also revealed a humbling truth: Earth’s oxygen-rich era may only represent 20-30% of its total lifespan. So while we’ve got time, the clock is ticking—just not fast enough to lose sleep over yet.
