Conservation by America is not going to decrease global warming. We need to imitate known global-cooling events, such as the Krakatoa volcano explosion, which spread sunlight-reflecting dust into the stratosphere in 1883. A hydrogen bomb exploded inside a ship full of white clay could be a first step.

Daniel Shanefield
Honolulu, Hawaii

Recent research suggests that cooling Earth by injecting large amounts of aerosols high in the atmosphere could cause average rainfall worldwide to decrease dramatically, as it did for more than 16 months after the eruption of Mount Pinatubo in 1991 (SN: 8/25/07, p. 125). —S. Perkins