On May 3, the Kilauea volcano erupted on Hawaii's Big Island. Since then, 18 fissures have opened in the earth, some hundreds of feet long. The USGS's Hawaii Volcano Observatory reports that some of these fissures are producing "lava fountaining, explosion of spatter bombs hundreds of feet into the air, and several advancing lava flow lobes." More than 2000 people have evacuated, and dozens of structures and vehicles have been destroyed. Five earthquakes have rattled the island as well.
Volcanoes are amazing portals to the hot, living interior of the Earth, but they're also dangerous. Even small-ish ones can have a global impact. Here are 15 explosive facts about volcanoes.
1. THE VOLCANIC EXPLOSIVITY INDEX MEASURES THE STRENGTH AND SIZE OF ERUPTIONS.
Created in 1982 by Chris Newhall of the United States Geological Survey and Stephen Self of the University of Hawaii, the VEI quantifies the strength of volcanic eruptions by measuring the volume of pyroclastic material spewed by a volcano, including volcanic ash, tephra (fragments of volcanic rock and lava), pyroclastic flows (fast-moving currents of gas and tephra), and other debris. The height and duration of the eruption are also factored in. The scale ranges from 1 to 8, and each step indicates a tenfold increase of ejecta. Fortunately, there hasn’t been a VEI-8 eruption in the past 10,000 years.
