Since August, Iceland’s Bárðarbunga volcano has been spewing thousands of cubic feet of magma per second, from a fissure 28 miles (45 kilometers) from the central caldera. The thing about a volcano, says University of Cambridge geophysicist Robert White, is that “you can live 45 kilometers away, and molten rock might still pop up under your house.”
That's obviously a grave concern but far from the greatest one. Bárðarbunga is blanketed by Europe's largest (by volume) ice cap. If a vent opens under the cap, rapid ice melt could trigger devastating floods, and ash plumes miles high could ground air traffic across Europe, like the Eyjafjallajökull eruption did in 2010. As it stands, science still can't predict any of these scenarios, but Bárðarbunga could help. Prior to the eruption, White and his team had been tracking seismic activity in the area, namely the cracks caused by magma as it flowed beneath and through the crust. Armed with a true before-and-after data set, scientists may be able to better anticipate future eruptions. "That's going to be helpful for deciding when you have to move people away from an area," White says.