Volcanic sulfur dioxide linked to oxygen level rise in Earth’s early atmosphere
Study predicts 4.3% of oxygen in atmosphere today comes from breakdown of sulfur dioxide
A sudden increase in Earth’s atmospheric oxygen content occurred around 2.4 billion years ago and is known as the great oxidation event, but its origin remains an open question. Now, researchers in China have confirmed that the vacuum ultraviolet (UV) dissociation of sulfur dioxide into molecular oxygen and a sulfur atom was probably an important contributor.