The most recent experiment, which will most likely take place over a location in the American Southwest, sets out to see whether humans can replicate (on a much smaller scale) the effects of the 1991 Mount Pinatubo eruption in the Philippines, which spewed enough sulfur oxide into the stratosphere to lower the global temperature of the Earth by about 0.5 C for a year and a half. After releasing its cloud of chalk particles, the balloon will fly into the cloud and measure its effects.
If the Harvard experiment, called Scopex (Stratospheric Controlled Perturbation Experiment), is judged a success, it may be the first step toward the larger-scale operations described in the previous study published by researchers from Harvard and Yale, which outlines plans to build planes that will drop tons of sulfur oxide into the stratosphere en masse every few years.
Though the technique won’t remove the greenhouse gases already in Earth’s atmosphere or decrease the other environmental effects of industry, it might be able to lower the Earth’s temperature enough to buy the world time to enact more comprehensive plans to mitigate the more catastrophic effects of climate change, like the melting of the Antarctic ice shelves.
Though a number of scientists have expressed skepticism and fear about the unforeseen effects of this kind of geoengineering, Harvard professor and Scopex team member David Keith thinks that it could be a huge help: “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.”