Stratospheric Geoengineering… Huh?

In the Albedo post, I very briefly mentioned a strategy for slowing climate change via the injection of certain aerosols into the upper atmosphere in order to increase albedo (reflectivity of the Earth) and consequently lower global temperatures. The more scientific way to say all of that is Stratospheric Geoengineering, which specifically means the injection of sulfate aerosols into the stratosphere. To put it simply, the idea is to inject artificial clouds into the sky so that fewer rays from the sun reach the Earth, thus creating global dimming and slowing climate change.

While some scientists believe this promising solution could single handedly cool the planet, stop sea ice and glacial melting, and even halt sea level rise, many other scientists warn about consequences including drought, flooding, ozone depletion, grayer skies and, of course, financial improbability. As with many other proposed solutions, there are dozens of pros and dozens of cons, but determining which outweighs the other is proving very difficult.

A group of researchers at the Rutgers University released a theoretical study in 2009 entitled "The Benefits, Risks and Costs of Stratospheric Geoengineering," comparing themajor costs and benefits. They explain how the idea was originally meant to mirror the effects of volcanic eruptions, which release huge amounts of aerosols into the atmosphere and have been proven to cause small global temperature decreases. As far as financial probability goes, there is an expensive (but relatively cost effective) way to have airplanes inject the material into the stratosphere.

However, there are other gigantic negatives including proven ozone depletion which would greatly lengthen the life of the Antarctic ozone hole. Additionally, solar power productivity would decrease substantially due to decreased solar radiation. After Mount Pinatubo erupted in 1991, a study showed a 30-40% decrease in solar radiation in California for two years following the eruption. Since sulfate aerosols would obviously need to be injected and kept in the atmosphere constantly, even more ground would need to be made up for the decrease in solar power production.

As with many other climate change solutions, we see a negative feedback in which one solution causes the degradation of another. And because solar power prices are decreasing rapidly, now would not be the ideal time hamper productivity potentials. Perhaps scientists will find a different type of aerosol to increase albedo and decrease climate change. Until then, stratospheric geoengineering appears to be an unfavorable and unlikely solution.