A Slowdown in Earth’s Rotation Could Have Affected the Oxygen Content of the Atmosphere

[Grim Reaper 6]

Virtually all oxygen on Earth was and is produced by photosynthesis, which was invented by tiny organisms, the cyanobacteria, when our planet was still a rather uninhabitable place. Cyanobacteria evolved more than 2.4 billion years ago, but Earth only slowly transformed to the oxygen-rich planet we know today. “We do not fully understand why it took so long and what factors controlled Earth’s oxygenation,“ said geomicrobiologist Judith Klatt. “But when studying mats of cyanobacteria in the Middle Island Sinkhole in Lake Huron in Michigan, which live under conditions resembling early Earth, I had an idea.”

When the Earth-Moon system formed, days were much shorter, possibly even as short as six hours,” Arbic explained. Then the rotation of our planet slowed due to the tug of the moon’s gravity and tidal friction, and days grew longer. Some researchers also suggest that Earth’s rotational deceleration was interrupted for about one billion years, coinciding with a long period of low global oxygen levels. After that interruption, when Earth’s rotation started to slow down again about 600 million years ago, another major transition in global oxygen concentrations occurred.

Overall, the two major oxygenation events (jumps in oxygen concentration) in Earth’s history – the Great Oxidation Event more than two billion years ago and the later Neoproterozoic Oxygenation Event – might be linked to increasing daylength. Hence, increasing daylength could have boosted benthic net productivity sufficiently to impact atmospheric oxygen levels. “Juggling with this wide range of temporal and spatial scales was mind-boggling – and lots of fun,” Klatt concludes. 

https://scitechdaily.com/a-slowdown-in-earths-rotation-could-have-affected-the-oxygen-content-of-the-atmosphere/