Plumes of volcanic ash disrupting air traffic.

• Position: YOUR LIFE

The jet stream--region in the atmosphere that pilots prefer to fly in--seems to be the area most likely to be impacted by plumes of volcanic ash, as has been demonstrated from the cloud that has drifted from the Eyjafjallajoekull volcano of Iceland, which recently endured two eruptions within the space of a month.

'That's a problem because modem transcontinental and transoceanic air routes are configured to take advantage of the jet stream's power, saving both time and fuel," explains Marcus I. Bursik, professor of geology in the University at Buffalo (N.Y.) College of Arts and Sciences. "The interaction of the jet stream and the plume is likely a factor here. Basically, planes have to fly around the plume or just stop flying, as they had to, as the result of this eruption in Iceland."

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In some cases, if the plume can be tracked well enough with satellites, pilots can steer around it, he notes, but that did not work in this case because the ash drifted right over Britain in mid April.

Bursik participated in the first meetings in the early 1990s between volcanologists and the aviation industry to develop methods to ensure safe air travel in the event of volcanic eruptions. He and colleagues authored a 2009 paper in the Journal of Volcanology and Geothermal Research. "In the research we did, we found that the jet stream essentially stops the plume from rising higher into the atmosphere," he points...