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Winter morning sunrises leave Mt. Redoubt colored soft and pink, but its gentle hues may belie its violent potential.

In the Alaska Volcano Observatory's Nov. 7 update, the 10,197 foot volcano on the west side of Cook Inlet had its aviation color code raised to yellow and its alert level upped to "advisory."

For now, Peter Cervelli and John Power, geophysicists with AVO, both agree, Redoubt only requires continued monitoring.

"There's no reason to believe that this unrest will result in an eruption. Right now we're keeping a good eye on it," Cervelli said.

The mountain isn't releasing plumes of ash, hazardous to aircraft operating nearby. Mike Fergus, spokesman for the Federal Aviation Administration in Renton, Wash., explained that if the volcano were to begin emitting ash, the FAA would be notified, and pass that information along to end user groups, including both commercial and private aircraft operators.

Cervelli said if local pilots notice any increases in activity on the peak they should contact the observatory.

In the past two months Redoubt has shown increased gas emissions and thermal activity compared to its normal background levels.

Cervelli explained that in October and November, the observatory did a fly-over to observe physical changes on the peak and test for gasses released by the volcano. Cervelli said the tests showed significant increases in emissions.

Additionally, Cervelli noted physical changes on the mountain including bare patches of ground where there would typically be ice and snow, increased activity near the gas vents, called fumaroles, and a small collapsed hole in the Drift Glacier.

Earthquake activity on the peak has remained relatively low despite the apparent and atmospheric changes.

"There's been a modest increase in seismicity, but Redoubt is a busy volcano seismically because of ice movement up there," Cervelli said.

The increased activity may or may not be indicative of things to come. Cervelli pointed out that in 2004, Mt. Spur, northwest of Tyonek, showed signs of increased activity but ultimately fizzled without an eruption. In 2006 however, Mt. Augustine, in Cook Inlet, showed similar activity resulting in an eruption.

"I'm not saying it's 50-50 by any means," Cervelli said. "I wouldn't give a prediction, but what I do know is Redoubt is pretty active. It's erupted once every 30 years or so."

The mountain has showed a tendency to erupt on somewhat of a schedule, with reports dating back to 1902. Its most recent eruption was in 1989 through 1990.

"We're at 20 years, it might be a bit early but they're not bus schedules," Cervelli said of the volcanic eruption cycles.

AVO is adding monitoring equipment to the peak to better track the activity.

"We took this opportunity to get our existing network in tip-top shape," Cervelli said.

A hut between 4,000 and 5,000 feet up the mountain is used to station observation equipment. New additions will include a web camera, a seismometer and a global positioning satellite receiver. Cervelli said recent foul weather has prevented AVO from completing installations, but they hope to have everything set up in the coming days.

While the three new installations will all help AVO better monitor changing conditions on Redoubt, the GPS receiver may be the key to predicting an eruption.

"When you have continuous measurement of ground deformation that you'd get with a GPS receiver it enables you to determine with a fair degree of certainty if new magma has intruded into the upper crust," Cervelli said.

Such an event, Cervelli explained, would be a telltale sign that an eruption was in the works.

When Redoubt last erupted such technology wasn't yet available. The GPS will ideally allow the observatory more time to notify surrounding communities of an eruption if one is imminent.

Cervelli called the last eruption "significant," noting damage caused by lahars and ash clouds. The lahars, or volcanic flooding, resulted in damage to the Drift River Oil terminal at the base of the mountain. Ash was deposited up to five millimeters deep in some places on the peninsula.

Power, who was working at AVO when Redoubt last erupted, said that monitoring began after the mountain had begun to steam and show levels of activity.

"What happened in '89 was elevated levels of earthquake activity and reports of steaming," Power said. "Our monitoring on Redoubt at that time was brand new.

"Consequently, through that early period of September through November, we were aware that there was activity, but we couldn't say if it was new or old."

In December however, the activity on the mountain suddenly ramped up, with a 23-hour period of high levels of earthquake activity followed by an eruption.

"It did come on very quickly, that's kind of the worry now, though the current activity is mild," Power said.

Visit the Alaska Volcano Observatory online at http://www.avo.alaska.edu/.

Dante Petri can be reached at dante.petri@peninsulaclarion.com.