Don't panic, but keep alert if you have trans-Atlantic travel plans in the next few weeks. The Icelandic Meteorological Office has reported a sudden flurry of small earthquakes that could be a prelude to an eruption of Bardarbunga, one of the country's largest volcanoes.
A full-scale eruption, such as occurred in April 2010 at the Eyjafjallajokull volcano, can send a huge plume of smoke and ash into the air; depending on wind and air currents at the time, it can stick around, disrupting air traffic for days or weeks. In 2010, the disruption lasted nearly a month.
More details in this story from CBC.CA