The planet is cleaning itself, and our estimates of global climate change are wrong
It's no secret to scientists that the planet itself absorbs carbon from the atmosphere through the oceans. In fact, this function is taken into account in models designed to help us predict the far-reaching consequences of global climate change due to atmospheric pollution (primarily carbon emissions). Except that it was previously thought that almost all of the carbon trapped by the oceans is returned to the atmosphere with volcanic eruptions.
There is only one way carbon is drawn deep inside the Earth: plate subduction: the slow collision and deformation of tectonic plates that causes the planet to absorb both biological remains containing carbon and atmospheric carbon.
New research shows that the Earth absorbs more carbon from the atmosphere than scientists previously thought. They simulated chemical reactions occurring in tectonic plates using the European Synchrotron Radiation Particle Accelerator. Scientists were able to create intense pressures and super-high temperatures in subduction zones, simulating what happens in the Earth's interior.
Specifically, the team found that carbonate rocks become less calcium-rich and more magnesium-rich on their way deep into the mantle, making them less soluble, further reducing the potential for them to return to the atmosphere through volcanic eruptions.
Instead, more of the carbonates appear to sink deeper and may eventually become diamond, taking with them the carbon collected from the atmosphere through the oceans. It is now clear that about a third of the carbon absorbed remains locked up forever.
This discovery will change the equations designed to predict climate change, but it doesn't mean we can breathe a sigh of relief.
This process alone is far from saving our rapidly warming planet from a climate crisis, but a better understanding of the carbon cycle between the atmosphere, the oceans and the Earth's interior should prove useful in charting a future course. If we do get a little more time, it would be good to use it to our advantage.