VOLCANO MADNESS: [Geology2] Cleveland Sends Up 35,000ft Ash Cloud

Wednesday, June 20, 2012

[Geology2] Cleveland Sends Up 35,000ft Ash Cloud

Cleveland Sends Up 35,000ft Ash Cloud

By Mike Mason & Stephanie Joyce

Tuesday, June 19 2012

Cleveland Volcano sent up its largest ash plume since 2001 on Tuesday afternoon. A pilot flying in the vicinity estimated the height of the plume at 35,000, although Alaska Volcano Observatory geophysicist Dave Schneider says that's a rough guess.

"[It depends] on [the pilots'] perspective - the accuracy really depends on how far away they are and which way the plume is blowing etcetera. We also saw the explosion on our distant seismic network and it appears to be short duration, on the order of several minutes, so it's not a very significant event and it's unlikely to cause much disruption to aviation."

Schneider says this is just the latest in a series of minor eruptions of Cleveland, which is on uninhabited Chuginadak Island, about 115 miles west of Unalaska.

"Early in the eruption, which started last July, July through about December, the pattern was slow eruption of lava in the summit crater. That has switched after that [lava dome] got blown out by some explosions in late December and there have been some other minor lava emissions, but the recent activity, since about the first of the year, has been occasional, small explosions lasting on the order of minutes, putting up ash that's just mainly a factor local to the island."

Although the Volcano Observatory's webcam outside the nearby village of Nikolski captured the eruption, residents say they didn't feel, hear or smell anything and low-lying fog obscured views of the volcano.

Cleveland lies on a major international flight path and in light of Tuesday's eruption, the Observatory has raised the aviation alert level from yellow to orange.