As long-term global average temperatures steadily rise, and international efforts to address them steadily fall short, some scientists and engineers are working on increasingly desperate solutions to the symptoms of global climate change.

One approach to "geoengineering" the earth is to mimic the natural atmospheric cooling effect that tends to follow the massive dispersion of sulfur dioxide into the air during a volcanic eruption. There are a few obvious problems with this approach. For instance, it's unclear what nation or international body would be authorized to release the sulfur dioxide. The chemical is also a pollutant that can cause acid rain. It might indirectly both eat away at the layer of ozone that protects living things from ultraviolet light and warm the lower part of the stratosphere above the tropics, about 19 miles up.