To protect the world from dramatic warming, the greenhouse gas has to get out of the atmosphere. Researchers want to turn it into rock.

(Image: Project Vesta)

Of

Veronika Szentpétery-Kessler Tom Green’s name says it all: He green beaches. But not with trees, but with minerals: With the olivines, which are hardly known outside of specialist circles, he wants to capture CO2 from the air on a large scale and in this way slow down climate change.

The head of the non-profit Environmental organization Project Vesta has chosen two neighboring beaches as the first test area at an undisclosed location in the Caribbean. Ground olivine is to be applied to one of them this year. The waves rub the grains together, grinding them into small grains with a large surface. This accelerated weathering creates hydroxide ions that react with the CO2 in seawater to form hydrogen carbonate. This in turn later serves as building material for corals and shellfish. If their shell then sinks to the sea floor, it becomes limestone and other rocks, which store the CO2 for eons. It would only be free through geological activity.

“Reducing CO2 emissions will not be enough, we also have to remove the gas from the atmosphere,” says Green. Many researchers and the International Energy Agency are convinced that even if no additional CO2 were emitted into the atmosphere, global warming could no longer be stopped. Also the biologist, who after 18 years ago wanted to get involved in various tech companies for climate protection, after switching to technologies that enable such so-called negative emissions.

Access to all contents of heise + exclusive tests, advice & background: independent, critically sound c’t, iX, Technology Review, Mac & i, Make, c’t Read photography directly in the browser register once – read on all devices – can be canceled monthly first month free, then monthly 9, 95 € Weekly newsletter with personal reading recommendations from the editor-in-chief Start FREE month Start FREE month now Already subscribed to heise +?

Register and read Register now and read the article read immediately More information about heise +