The process is called “enhanced weathering” and it could potentially help capture gigatons of CO2 if it’s used in forests and on farms around the world.
Increased urgency to reduce atmospheric greenhouse gases has led to a rise in the number of reforestation projects aimed at cutting carbon emissions while greening up our planet. However, with limited land available to restore forests, these projects alone won’t be sufficient to pull excess CO2 out of the atmosphere.
That’s why a startup called The Future Forest Company is trying out something new: spreading crushed basalt rock on the ground of a birch and oak forest on the Isle of Mull, in Scotland. The process is called “enhanced weathering” and it could potentially help capture gigatons of CO2 if it’s used in forests and on farms around the world.
The startup also works on reforestation projects, but the team realized that solely restoring forests doesn’t go far enough to significantly reduce CO2 emissions. “The problem that you come up against with reforestation is the scale — basically, there’s just not enough land on the planet to remove the emissions we need to remove through reforestation alone,” says Jim Mann, the founder of Future Forest. As a result, the company decided to explore enhanced weathering as a way to help fill the gap.
As explained by Fast Company, enhanced weathering speeds up a natural process. When rain falls through the atmosphere, it dissolves CO2 in the air, forming a weak carbonic acid. When that acid touches basalt, it reacts to form a carbonate mineral that stores carbon dioxide. “Effectively, when that process has occurred, the carbon dioxide is locked up for hundreds of thousands or even millions of years,” Mann says.
By crushing the rock into dust and spreading it onto the surface of a forest or farm, it increases the contact between rain and the basalt, accelerating the process of carbon sequestration.
While previous trials suggest that it works, the new project is the first one to test it in a much larger area. The team behind the test in Scotland expects to have early results about whether the process works soon, though it will keep running a longer-term study to observe whether there are unanticipated results.