If everything can be worked out, three researchers from Harvard are hoping to start testing their idea of reducing the level of sunshine that the Earth receives. This will hopefully cool off the planet when it starts to heat up as a result of climate change. They are hoping to spray calcium carbonate particles directly into the stratosphere. Their project would actually be the very first of its kind to be implemented in the sky.
This radical idea is quite controversial to say the least. Even the research team itself, which consists of Zhen Dai, Frank Keutsch, and David Keith have their doubts about the entire thing. Environmentalists are very worried that these kinds of geoengineering climate fixes will prove to be a distraction from more effective solutions that involve a more intelligent consumption of these kinds of carbon-producing materials. They are especially concerned about the manipulation of the planet’s complex natural balance as it could result in lots of unpredictable consequences. This would be yet another case of putting way too much faith in engineering, which actually created this mess to begin with.
The SCoPEx Experiments
SCoPEx is what this Harvard research team is calling this project as it is short for “Stratospheric Controlled Perturbation Experiment.” The plan begins with launching two balloons that are steerable over the Southwest region of the United States. Each of these balloons will spray roughly 100 grams of calcium carbonate directly in the stratosphere. Each of the particles are about 0.5 micrometers in size as the researchers believe that’s the perfect size for both dispersing and reflecting sunlight.
It sounds simpler than it really is. For starters, the balloons will need to turn around so they can observe what they have left behind them. Secondly, they will have to have a precise means of detection that can locate the plume of calcium carbonate plume and then measure both the size and the quantity of particles. A team at NOOA’s office in Boulder, CO that is led by David Fahey will provide the needed equipment to perform these measurements, but Fahey cautions, “It’s going to be a hard experiment, and it may not work.” And finally, the balloons need to recapture a few particles before they return to the ground. The balloons might even a laser onboard to help conduct the needed tasks.
The notion of injecting particles directly in the upper atmosphere isn’t a new idea, but this would definitely be the very first attempt to actually do it. Scientists really believe this idea will work because it takes place naturally after the eruptions of volcanoes. One example of this was during the Mount Pinatubo eruption that took place in the Philippines in the year 1991. That eruption injected approximately 20 million tonnes of sulfur dioxide which actually cooled off Earth by about 0.5° for a period of 18 months.
By switching to calcium carbonate for the SCoPEx project will reduce the damage that sulfur inflicts on the ozone layer. The SCoPEx experiment is very limited in scope, and Dai explains, “I’m studying a chemical substance. It’s not like it’s a nuclear bomb.” But there is still the concern about playing around with sunlight and the atmosphere and sunlight. Primary investigator Keutsch comments, “There are all of these downstream effects that we don’t fully understand.” The fact remains that solar engineering can severely disrupt the precipitation patterns of nature. This could lead to both deluges and droughts. Even though plants experience less heat stress in darker, cooler environments, they don’t get as much sun either. Keith remains cautiously optimistic, however, stating, “Despite all of the concerns, we can’t find any areas that would be definitely worse off. If solar geoengineering is as good as what is shown in these models, it would be crazy not to take it seriously.”
However, one thing about the choice of using calcium carbonate is that it is not a chemical that naturally exists in the stratosphere, where SCoPex aims to spray it. “We actually don’t know what it would do, because it doesn’t exist in the stratosphere,” states Keutsch, “That sets up a red flag.” When he first found out about SCoPex’s research, he says that he thought it was “totally insane.”