The Alaska Volcano Observatory yesterday downgraded the aviation warning code for Mount Redoubt from orange to yellow and the alert level from Watch to Advisory. Alert levels had been high since Mount Redoubt’s most recent rumblings starting March 15. The most dramatic eruptions happened between March 22 and April 4 when the volcano spewed ash, gas and steam up to 65,000 feet high. High level winds carried ash to Talkeetna, Skwentna and Trapper Creek while air traffic came to a halt for a few days.

After April 4, Redoubt continued to erupt, creating a lava dome in the summit crater. A lava flow now extends nearly 0.6 mile down the north flank of the volcano.

AVO reports that observations from overflights, webcam and satellite imagery have not been able to detect changes caused by dome growth for the past three weeks. However, the dome is unstable and AVO scientists warn that a collapse could be accompanied by the production of a large ash plume in the Drift River valley.

Lava flow has slowed significantly and may even have stopped, prompting AVO to downgrade the aviation color code to yellow and the alert level to advisory. Advisory means that volcanic activity has decreased but continues to be closely monitored for possible renewed increase. Seismic activity slowed down as well, but is still higher than normal. AVO had staff monitoring Redoubt around the clock, but now transitions employees off the 24/7 shifts.

Story by Diana Haecker

Mt. Redoubt 1/27

Mt. Redoubt started to rumble this past weekend. The Alaska Volcano Observatory and others are watching the volcano 24 hours a day. Mat Su Borough officials are putting in place their emergency preparedness training and setting up a website specific to the possible ashfall. Residents can also look at the Alaska Red Cross page and NOAA for information.  story first run 1/30

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News reports of Mount Redoubt’s possible eruption were featured on Yahoo, Google, CNN and other websites, all of which included the link to the Alaska Volcano Observatory website. The agency was expecting internet traffic, since they experienced the same thing with St. Augustine several years ago. The scientists had a low bandwidth version in place for the extra traffic, but the system still crashed.

Basic information is now available on the simplified website, but it doesn’t have the fancy maps, wind trajectories and cameras it had previously. Technicians are working on distributing the higher bandwidth to other servers.

According to the Alaska Volcano Observatory, a typical Redoubt eruption features a large explosion that can shoot ash clouds 40,000 feet high. During the last eruption, in April 1990, the ash plume disrupted air travel and sent ash across the state.