To cool the planet without ozone damage, scientists aim to mimic the natural cooling effect that happens after a massive dispersion of sulfur dioxide into the air during a volcanic eruption. A giant antacid tablet for Earth may just do the trick, a new study suggests.
'Geoengineering' May Not Just Be A Sci-Fi Idea Anymore
Researchers from the Harvard John A. Paulson School of Engineering and Applied Sciences suggest that "geoengineering" - or using chemicals to slow down global warming - could tackle the Earth's growing climate change problem. This could be achieved by pumping an aerosol of calcium carbonate.
Frank Keutsch, co-author of the study said: "Instead of trying to minimise the reactivity of the aerosol, we wanted a material that is highly reactive but in a way that would avoid ozone destruction. Essentially, we ended up with an antacid for the stratosphere."
This study opens atmosphere-seeding options beyond sulfur dioxide, which has caused debates inside and outside of the scientific community. Researchers say that turning to a calcium compound that's among the most common on earth "could have significantly less environmental risk than sulfate aerosol."
Calcite Could Reverse Ozone Loss
This new study uses aerosols that are highly reactive and not hazardous to the ozone layer. Researchers discovered that calcite - a composition of limestone - could possibly reverse ozone loss, because it neutralizes emissions resulting from acids in the atmosphere while reflecting light and cooling the planet.
"Calcite is one of the most common compounds found in the earth's crust," said David Keith, first author and Harvard professor. "The amounts that would be used in a solar geoengineering application are small compared to what's found in surface dust."
More research is needed, though. Scientists claimed that these experiments could result in unanticipated aftermaths and that they still do not know the full effects of "geongineering".