Scientists Found Particles That Could Repair Ozone Layer Damages

Researchers from the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) have identified another way to help reduce rising global temperatures, by injecting light-reflecting particles in a process called solar geoengineering.

It is well-known that amounts of aerosols can significantly cool the planet, but these sulfate aerosols can also damage the ozone and as a result, may lead to skin cancer and eye damage in humans.

Now, the researchers have found a different kind of aerosol that is effective and at the same time safe.

"Anytime you introduce even initially unreactive surfaces into the stratosphere, you get reactions that ultimately result in ozone destruction, as they are coated with sulfuric acid," said Frank Keutsch, the Stonington Professor of Engineering and Atmospheric Science at SEAS and a co-author of the paper, said in a statement.

"Instead of trying to minimize the reactivity of the aerosol, we wanted a material that is highly reactive but in a way that would avoid ozone destruction," Keutsch added.

Science Alert reported that the researchers looked for particles that could neutralize the acid on the surface, and eventually found calcite, a constituent of limestone, which can neutralize emissions-borne acids in the atmosphere, reflect light and simultaneously repaire ozone damage.

"Calcite is one of the most common compounds found in the Earth's crust," said David Keith, the Gordon McKay Professor of Applied Physics at SEAS and professor of public policy at the Harvard Kennedy School and the first author of the paper. "The amounts that would be used in a solar geoengineering application are small compared to what's found in surface dust."

New Atlas reported that the researchers had already conducted laboratory tests that simulate stratospheric conditions to see if it will work. However, they also noted that there are a lot of ethical, political and environmental consequences we need to consider before pushing the go signal to this proposal.

"Geoengineering is like taking painkillers," said Keutsch. "When things are really bad, painkillers can help but they don't address the cause of a disease and they may cause more harm than good. We really don't know the effects of geoengineering, but that is why we're doing this research."

The research, published in the Proceedings of the National Academy of Sciences is supported by the Fund for Innovative Climate and Engineering Research and the Star Family Challenge for Promising Scientific Research.