Wednesday, June 13, 2012
Paul Crutzen, the 1995 Nobel Prize winner in Chemistry for his work on the ozone layer, has proposed injecting sulfur into the atmosphere so less sunlight will penetrate it. Artillery guns on high-altitude balloons would be used to fire sulfur into the atmosphere. There is historical precedent. "When Mt. Pinatubo in the Philippines erupted in 1991, it sprayed millions of tons of sulfur into the atmosphere. Much to scientists' surprise, the sulfur reflected so much sun that the Earth’s surface cooled by almost one full degree Fahrenheit in the year following the eruption." This could work, but only temporarily since sulfur only stays in the atmosphere for a couple of years while carbon dioxide lingers for over a century.