Iceland officials have raised the threat of that country's Bárðarbunga volcano eruption to code orange, the second highest level before an event. While the risk isn't critical at the moment, past Icelandic volcanos have gotten seriously rowdy with the planet, and no one is taking any chances. Over the last few days hundreds of minor earthquakes, referred to collectively as an earthquake swarm, have been detected underneath the island. The area north of Bardarbunga has been evacuated because officials "could not rule out an eruption." Reports thus far have ranged from breathless to measured.

Bárðarbunga, a subglacial volcano located under the Vatnajökull glacier in Iceland, hasn't exhibited any signs that its magma is moving toward the surface just yet, which geologists tell us is a good thing. Still, even a minor eruption could cause glacial melting and subsequent flooding, and a massive one could prove cataclysmic.

In 2010, Iceland's sexily named Eyjafjallajökull volcano erupted, spewing ash into the sky that halted much of Europe's air travel for six days, affecting an estimated 10 million people and costing an estimated $1.7 billion.

But the mother of all was the Laki eruption of 1783-84. The event plumed gases into the air, eventually directly or indirectly killing 60 percent of the country's livestock, 22 percent of its human population, and possibly lowering temperatures in the northern hemisphere by 1.3 celsius for several years after. Of the 122 metric tons of sulfur dioxide emitted from that eruption, 95 made it into the upper troposphere and lower stratosphere, hit the jet stream, and circulated across the northern hemisphere. The stuff spread across Europe, forming what was called the Laki Haze, which damaged crops and reduced livestock. The haze was seen as far as Italy, China, and possibly Alaska (records from that time are scant), where a noted population decrease transpired in the years following, and the Inuit speak of the "Summer that did not come," which may correlate with the disaster.

Yikes! Let's hope this is just some indigestion.