Checking the faster warming of Earth is imperative to ensure mankind's survival. Paris climate agreement rightly mandates that global temperatures should not exceed 1.5 degrees Celsius beyond the preindustrial levels.
However, there are doubts that mere emission reduction alone will not cure the planet's warming. In a new method to cool the planet, way beyond curbing of greenhouse gas emissions, a new study is offering solar geoengineering as a solution that seeks to inject light-reflecting sulfate aerosols into the stratosphere to cool the Earth.
Safe Aerosol To Cool The Planet
The idea is from researchers at Harvard University's John A. Paulson School of Engineering and Applied Sciences who are offering a safe aerosol to cool the planet without causing damage to the ozone layer.
The research is published in the Proceedings of the National Academy of Sciences.
The new aerosol addresses the conventional risks of sulfuric acid production in the stratosphere, and the Harvard experts call it a "drastic idea."
Protecting the ozone layer is crucial, as it is the main absorber of ultraviolet light from the sun. Any rupture of the ozone layer can be fatal and can bring unpleasant consequences to people, including skin cancer, eye damage, and other problems.
Turning Point In Solar Geoengineering
Calling the new research a turning point in solar geoengineering, David Keith, the Gordon McKay Professor of Applied Physics at SEAS and the first author of the paper, explained the highlights of the new aerosols.
"In solar geoengineering research, introducing sulfuric acid into the atmosphere has been the only idea that had any serious traction until now," said Keith.
However, the new research takes a look on particles used in solar geoengineering, notes Frank Keutsch, coauthor of the paper and Stonington professor of engineering at SEAS.
Instead of limiting ozone-damaging reactions of nonreactive aerosols, the new research seeks to reduce the reactivity of the aerosol itself.
The team comprising Keutsch, Keith, and coauthors Debra Weisenstein and John Dykema is targeting aerosols by introducing a material that is highly reactive yet poses no threat to ozone.
Strategy To Keep Ozone Safe
To keep the ozone safe, aerosol particles are sought to be neutralized to prevent sulfuric, nitric, and hydrochloric acid formation on the surface.
They chose calcite after a modeling exercise as the remedy to counter ozone loss by neutralizing the acids and for reflecting light to cool the planet.
Calcite is a commonplace compound found in the Earth's crust, added Keith. The researchers have tested calcite in lab conditions for stratospheric applications and are satisfied with the results.
Despite the promising research, Keith and Keutsch cautioned that stratospheric chemistry is a complex area, and aerosols must be seen like painkillers seeking to lessen the pain of a warming Earth.