By Our Reporter
We may never live to see it, but the skies of Earth could one day run out of oxygen. A new supercomputer simulation paints a picture of a future that’s hard to envision — a world without breathable air, and with it, the extinction of most known life.
Simulation foresees steep drop in oxygen
Scientists at Toho University in Japan operated a huge planetary model, based on NASA’s climate data, to model Earth’s atmospheric future. The outcome? Oxygen will be gone in approximately one billion years, rendering survival impossible. The researchers conducted 400,000 simulations to examine how Earth’s atmosphere could change over time.
As the sun ages further, it will expand and get hotter and brighter. This change will heat the world, heating up surface temperatures and causing water to evaporate. Plants will perish as the carbon cycle diminishes, ceasing oxygen production completely. The outcome would be an atmosphere of methane — as it was during the planet’s early days prior to the Great Oxidation Event.
Oxygen loss will change life forever
The research, published in the journal Nature Geoscience, is entitled The future lifespan of Earth’s oxygenated atmosphere. It reveals the oxygen-rich stratum on which we depend will disappear much earlier than was long thought. “The study follows from longstanding ideas in the geoscience literature on solar brightening and geochemical cycles,” said Kazumi Ozaki of Toho University, an assistant professor.
For decades, scientists thought Earth’s biosphere would run out in about two billion years. This was expected to occur because of overheating and the absence of COâ‚‚ for photosynthesis by plants. But Ozaki’s team discovered that oxygen concentrations could decline much earlier — within one billion years.
He said that whereas the previous models indicated gradual decline, this simulation indicates a sharp and sudden transformation. When the levels of COâ‚‚ come down and temperatures increase, the world will no longer be able to sustain intricate life forms. Although life may persist, it would be radically different from the one we have now.
A distant yet inevitable fate
Ozaki emphasized that the loss of oxygen on the planet is connected to Earth’s and the sun’s natural cycle. Although this future is well beyond human existence, the discovery aids scientists in understanding planetary habitability — not just for Earth, but for hunting life elsewhere.
Although we will not be around to see this quiet end, this research reminds us of the fine balance that sustains our planet today.
