This column is provided as a public service by the Geophysical Institute, University of Alaska Fairbanks, in cooperation with the UAF research community. Ned Rozell is a science writer at the institute.
Volcanoes often wake in one of two moods.
Some explode, launching rocks the size of minivans and shooting ash miles into the atmosphere. Others stretch, belch a few gases, and ooze molten rock. A new project in Japan might help scientists predict which way a volcano will behave when it stirs from a long slumber. Explosive eruptions grab more attention than effusive eruptions, during which lava flows from a vent without much of a pyrotechnics show. One of Alaska's most famous explosive eruptions was Mt. Katmai in 1912, which in two days spewed more than 30 cubic kilometers of pumice and grit into the air.