Scientists Say Sun-Dimming Could Help Climate Change

Bruno AmaruFlickr/CC BY-NC-ND 2.0

A new paper published on Monday in Nature Climate Change suggests that it’s possible to cool the planet and curb the harmful effects of climate change by blocking the sun. In particular, Harvard University Scientists claim that researchers can inject aerosol chemicals into the atmosphere to decrease global temperatures. The caveat is that only enough aerosols to reduce approximately half of the Earth’s warming should be used, as per Mashable.

The reason for employing half measures is to reduce the adverse impacts on the atmosphere. Any study that suggests a potential way to drastically alter the climate is going to also hold the potential to harm the Earth. But the new study shines a light on the potential of geoengineering—which tends to cause lots of hesitation due to side effects like changing hurricane season and precipitation patterns—when it’s used in moderation.

While most geoengineering research focuses on curbing all of the warming effects that stem from greenhouse gas pollution, the new study uses high-resolution climate models to double carbon dioxide, according to Gizmodo. Afterward, the team decreased levels of incoming sunlight to the point where it balanced approximately half of the warming that was associated with increased carbon pollution.

“Surprisingly we find only a very small fraction of places see the effects of climate change exacerbated,” lead study author Peter Irvine told Gizmodo.

“If you kept cooling, you’d keep getting benefits of temperature but diminishing returns on hydrological variables. Offsetting all warming, and you’re beginning to introduce problems that are new.”

Although the results are akin to taking two steps forward and one step backward, Irvine says that the intervention could create great benefits.

“The analogy is not perfect but solar geoengineering is a little like a drug which treats high blood pressure,” he told The Independent.

“An overdose would be harmful, but a well-chosen dose could reduce your risks.”

he sun setting behind the wind turbines of Burbo Bank Offshore Wind Farm in Wallasey, England.
Featured image credit: Christopher FurlongGetty Images

Of course, the study is not a be-all and end-all solution and should be taken with a grain of salt.

“[T]he study would have been more policy-relevant if it concentrated on a realistic (transient) global warming scenario and represented solar geoengineering using stratospheric aerosols,” Anthony Jones, an aerosols researcher who published a separate paper on geoengineering and hurricanes, told Gizmodo.

Jones suggests that the team should have instead looked at a scenario where pollution changes over a period of a century as opposed to doubling carbon dioxide abruptly. In his mind, this would create results that are more decision-oriented. However, he does agree that the study lends support to the effectiveness of using “a moderate solar geoengineering application” for improving “most regional climate changes caused by global warming.”

Regardless of the study’s conclusions, sun-dimming is a potential solution that still requires lots more research before it’s tested in the real world. Hopefully, the results will help researchers continue to piece together the puzzle.