[Paul C. Jesup]

There have been about 30 Pinatubo scale-eruptions at Yellowstone in the past 600 thousand years as well. Chances are much more likely we'd see one of those lesser blowups in our lifetimes.

When, where and how powerful was the Pinatubo eruption?

[Kevin Curry]

Pinatubo erupted in June 1991. It is located on the Phillipine Island of Luzon (just north of Manila and Clark Air Base). It was about ten times more powerful than Mt. St Helens. It spread sufficient dust and sulfur dioxide into the atmosphere to cause drop in global temperatures of about a half a degree centigrade for two years. I still recall the very vivid red sunsets of that period.