Earthquakes near the volcano since 16 August (more recent in red).

Earthquakes near the volcano since 16 August (more recent in red).

Icelandic Meteorological Organization

Bárðarbunga awakes

After a week of rumbling, Iceland’s Bárðarbunga volcano began erupting yesterday, say scientists at the Icelandic Meteorological Office (IMO) in Reykjavik—although the eruption remained entirely under the thick ice covering the volcano. Bárðarbunga is located beneath the giant Vatnajökull glacier in the center of the island; this particular eruption is occurring under a northern offshoot, the Dyngjujökull glacier. Although no magma or ash reached the surface, IMO raised the country’s aviation code from orange to red, indicating that an eruption is imminent or in progress.

IMO recorded seismic tremors—small, continuous, almost rhythmic earthquakes thought to be related to the interaction between lava and ice—at 11:15 GMT. Then, a stronger seismic swarm occurred at about 2:10 p.m. GMT; at that time, IMO’s daily status report noted, “[t]he frequency of earthquakes is so high, that the events are overlapping in time, and it is difficult to discern individual events.” IMO scientists concluded that the magma was melting the ice atop the volcano. But, as the thickness of the ice over the volcano (between 100 and 400 meters) and the volume of lava are both unknown, it’s also unclear whether an eruption will break through the ice, or whether it will remain subglacial. Yesterday evening, IMO noted on its website that “there are no signs of ongoing volcanic activity,” but the alert will remain red for the time being because “an imminent eruption can not be excluded.”

View Bárðarbunga live here.