Scientific models examine the history and future of Earth's atmospheric oxygen

New scientific research is providing deeper insights into the history and future of Earth’s atmospheric oxygen. A study published in Nature Communications suggests that ancient ocean chemistry played a vital role in maintaining oxygen levels following the Great Oxidation Event approximately 2.3 billion years ago. Researchers found that a cycle involving phosphorus and sulfate helped sustain life-supporting conditions; microbes used sulfate to recycle phosphorus, which fueled biological growth and subsequent carbon burial, allowing oxygen to accumulate.

In a separate study published in Nature Geoscience Research, scientists from NASA, the University of Tokyo, and the University of Bristol used supercomputer modeling to project the long-term stability of Earth's oxygen-rich atmosphere. The models predict that the lifespan of oxygen-based biosignatures is tied to the Sun's expansion. The research estimates that in approximately 1 billion years, increasing solar heat will render the planet uninhabitable by reducing oxygen levels and creating a hostile environment.