Volcanic danger in Alaska: Volcanic eruption could bring air travel to standstill

[Laidback Al]

Volcanic eruption could bring world to standstill

NED ROZELL
ALASKA SCIENCE
Published: April 23rd, 2011 04:21 PM
Last Modified: April 23rd, 2011 04:51 PM

On a fine June day about 100 years ago, in a green mountain valley where the Aleutians stick to the rest of Alaska, the world fell apart. . . .

The great eruption that created the valley came from a smallish clump of rocks called Novarupta. Nowhere near as grand as the nearby Mount Katmai (the mountain that lost its top), Novarupta spewed an ash cloud 20 miles into the atmosphere, belching 100 times more ash than did Mount St. Helens.
Though few people know its name, Novarupta was responsible for the largest eruption of the 20th century. . . .

"Now the North Pacific is one of the busiest air corridors in the world," Welchman said. "More than 200 flights a day go overhead."
To calculate the effects of a modern-day Novarupta eruption on today's air travel, Welchman used a computer model called Puff developed by University of Alaska Fairbanks scientists and refined by research assistant professor Peter Webley of the Geophysical Institute.

She used the model to spew ash from Novarupta's vent once a week for five years. She wanted to see which airports in the world would be affected.

"Most airports in the Northern Hemisphere would close," she said. "Europe seems to get the brunt of it, but ash even reached Australia."
Welchman, who hopes to visit more Alaska volcanoes someday soon, summed up the return of Novarupta as follows:
"An eruption of Novarupta scale in today's society has the potential to bring the world to a standstill by affecting the majority of airports in North America and Europe for several days at least," she wrote on her poster. . . .

http://www.adn.com/2011/04/23/1824745/volcanic-eruption-could-bring.html

Bringing the world to a standstill: an investigation into the effects of a Novarupta scale volcanic eruption on today's aviation industry

Welchman, R. A.
American Geophysical Union, Fall Meeting 2010, abstract #V41E-2329

Novarupta erupted in Alaska on 6th June 1912 and was the biggest of the 21st century. It erupted for 60 hours and sent an ash cloud over 32,000m into the air. People were stranded for several days, houses destroyed, villages abandoned and food supplies disrupted for a long period after the eruption. Ash was recorded to have travelled over 9,500km away in Africa, demonstrating potentially global impacts. The eruption occurred when Alaska had very little aviation industry, today however the airspace above Alaska is one of the busiest in the world. The eruption in Iceland in 2010 which disrupted the European airspace for several weeks and closed it completely for five days, brought to light just how disruptive a volcanic eruption can be, even in countries where volcanic activity is not considered a hazard. It was an expensive event for the aviation industry and caused much disruption. Simulations of a Katmai scale eruption were run in the ?present-day?, using the PUFF ash fall model. Simulations were run for one week from the start the eruption. A ?worst-case? scenario is presented based on data from 2005-2009. It is a hypothetical eruption started on 17th January 2005 and it shows that ash is likely to cause havoc in North America, Europe and parts of Asia. At least 43 airports on average would be severely affected each day of the simulation, leading to several of the major air routes being affected. Where financial data is available, an estimated cost of this event is presented. A 500 hr simulation is presented to demonstrate the possible global effects that could occur within three weeks of an eruption. It shows ash being transported across the equator at high altitudes to the southern hemisphere in Asia as well as the whole of the northern hemisphere being engulfed. The complex implications an eruption like this would have on national and international infrastructures is presented. The results could aid further scientific studies, governmental bodies and industries on the effects of volcanic eruptions and provide information for hazard management.​

Keywords: [0545] COMPUTATIONAL GEOPHYSICS / Modeling, [8488] VOLCANOLOGY / Volcanic hazards and risks, [8499] VOLCANOLOGY / General or miscellaneous

http://adsabs.harvard.edu/abs/2010AGUFM.V41E2329W