Oxygen levels impacted past climate changes more than previously thought

Profile of the atmosphere and setting sun. (Credit: NASA)

The amount of oxygen in the atmosphere has played a role in climate changes throughout Earth’s history, according to a study from the University of Michigan. Though oxygen’s impact isn’t as drastic as carbon dioxide or methane, the findings prove that current climate models should be adjusted.

The study used computer simulations of past oxygen levels in Earth’s atmosphere, which varied from the 21 percent level of today’s atmosphere. They found that a lower oxygen level increased evaporation. The climate responds with rising temperatures and more precipitation. Increased oxygen caused the opposite response.

The researchers say this discovery is important for understanding changes of climates of the distant past that couldn’t be fully explained by carbon dioxide levels, but oxygen levels aren’t playing a significant role in present-day climate change.

Top image: Profile of the atmosphere and setting sun. (Credit: NASA)