Volcanic Havoc in the Air

The Icelandic volcano Eyjafjallajökull has filled a large swath of Europe's atmosphere with ultrafine ash, rendering the skies unfit for aircraft. The international air traffic system is well equipped for coping with volcanic ash plumes, thanks to the worldwide network of nine Volcanic Ash Advisory Centers. The London VAAC is in charge of the Icelandic sector, and you can easily access its latest maps and warnings.

The Iceland eruption is a fissure eruption, in which lava issues from a long, narrow vent instead of a simple hole in the ground. Hawaii is another place where fissure eruptions occur. In the geologic past, huge fissure eruptions are associated with large igneous provinces or LIPs. A LIP in India was largely responsible for environmental upsets around the time of the dinosaur extinction 65 million years ago, and the Yellowstone LIP has left a wide trail of lava plains across Idaho leading to the great caldera in Wyoming's northwest corner, our own "supervolcano."

By the way, it was Iceland that gave rise to Benjamin Franklin's most widely cited geological accomplishment, when he supposedly linked the 1783 eruption of Laki to the severe winter that followed. Um, not really. I think you could make a better case that Franklin was actually the father of borehole paleothermometry.

Background:
Volcanoes in a Nutshell
About calderas
An Oregon caldera
A model for supervolcano eruptions
The world's largest supervolcanoes
More volcanic links