Researchers led by Wei Shi at Chengdu University of Technology propose that variations in tectonic subduction helped drive major oxygen jumps in Earth’s history. By tracking temperature and pressure signatures in ancient subducted rocks, the team matched cooler subduction intervals with the three well‑known rises in atmospheric O₂, including the Great Oxygenation Event.

The model hinges on how carbon and sulfur, both oxygen‑hungry, are ferried into the mantle. When subducting slabs enter a hotter mantle, these elements release back to the surface via volcanism, scavenging atmospheric oxygen. Cooler mantle conditions trap more carbon and sulfur, limiting that loss and allowing O₂ to accumulate.

Data show low‑temperature subduction from 2.2‑1.8 billion years ago and again over the past 800 million years, aligning with the first, second and third oxygen spikes. This suggests that the efficiency of cold subduction on a cooling planet set a baseline for the oxygen budget, linking deep Earth processes to the breathable air we enjoy today.