• explosive eruptions;
  • fine ash

The 2010 eruption of Eyjafjallajökull volcano was not a large event. Over months of volcanic activity the ash plume never pushed above 10 kilometers, and the mass flows peaked at 1 million kilograms per second, feeble amounts compared to some other volcanic eruptions. In total, the volcano spewed out only 270 million cubic meters of ash—a single day's activity for some eruptions. By any conventional measure, Eyjafjallajökull lacked power. Nevertheless, the eruption had a tremendous effect on society, leaving tens of thousands of people stranded as air traffic around western Europe was shut down.