If the volcano is a-rockin', don't come a-knockin'
Imagine a typical volcano. Then picture a 16-mile-wide volcano that stretched from Philadelphia to 30 miles past New York City. Now imagine this gargantuan volcano squished under a thick ice sheet that would unleash a torrent of meltwater as soon as an eruption began. Finally, envision this super-massive, ice-encased volcano unleashing the largest lava flow on Earth in the last 12,000 years, and you'll probably have some idea as to why Iceland's authorities are sounding the alarm over the recent rumbling emerging from the Bárðarbunga volcano.
After the most powerful earthquake since 1996 struck the area early Monday — part of a swarm of thousands of smaller earthquakes indicating magma movement underneath Bárðarbunga — Iceland's meteorological office raised the threat of eruption to "orange," the second-highest alert possible (the highest alert is reserved for an active eruption). Officials are primarily concerned with the threat of a very large eruption damaging Iceland's extensive hydroelectric power grid.
So why should you be concerned with Bárðarbunga, non-Icelanders? One need only look back to 2010, when the ash plumes of Iceland's Eyjafjallajökull volcano caused airline chaos across Europe and the world, to see the far-reaching consequences of a major volcanic eruption. Still more alarming was the eruption of the nearby Laki volcano complex in 1783-4, which unleashed a cloud of highly toxic gas that killed 25 percent of Iceland's residents before killing thousands more in Europe. Bárðarbunga is Laki's big sister.
Care to monitor the volcano yourself? Here's a handy webcam of the (hopefully) snoring giant.