The Icelandic volcano that ramped up activity on April 13 could wreak havoc with European air traffic for some time.
Yet the Eyjafjallajökull volcano (pronounced AY-ya-fyat-la-yo-kult) is not the one most researchers have been keeping a wary eye on. Just a few kilometers to the east of the erupting vent is a much bigger and potentially more dangerous volcano called Katla. In the past, when Eyjafjallajökull erupted, Katla did too. So scientists are closely monitoring Katla to see if it, too, might go.
Volcanic activity is par for the course for Iceland, an island that is the above-water manifestation of the Mid-Atlantic Ridge, the seam of mountains running up the center of the Atlantic Ocean like stitches on a baseball. The ridge marks where magma wells up from deep inside Earth, giving birth to new oceanic crust that moves outward from the ridge.