Volcano monitors spot on with warnings

March 23, 2009 

A month after Louisiana Gov. Bobby Jindal complained about wasteful spending in President Obama's economic stimulus package, including money for "something called 'volcano monitoring,'" Alaska pilots were grateful for such expenditures.

The Alaska Volcano Observatory was ready with warnings to flight officials when Alaska's Mount Redoubt blew five times Sunday night and Monday morning, sending potentially deadly ash clouds north of Anchorage.

The volcano about 100 miles southwest of Alaska's largest city blew at night and even after sunrise was socked in by clouds, obscuring ash that can clog a jet engine and knock aircraft from the sky.

However, readings from seismometers and atmospheric pressure sensors alerted scientists that an eruption had occurred. Weather radar confirmed the presence of an ash cloud that ascended more than 11 miles above sea level.

"Without instruments in the ground, we would not have been able to tell you this was coming," said John Power, a geophysicist with the U.S. Geological Survey at the Alaska Volcano Observatory.

Volcano monitoring became a political issue when Jindal gave the Republican response to President Obama's message to Congress on the economic stimulus package. Jindal said the package was "larded with wasteful spending," including $140 million for volcano monitoring.

U.S. Sen. Mark Begich, D-Anchorage wrote Jindal and said volcano monitoring is a matter of life and death in his state. He made the point again after the eruptions. "I sleep better knowing the scientists are at work at the AVO keeping track of this activity," he said by e-mail.

The Alaska Volcano Observatory is a joint program between the USGS, the University of Alaska and the state Division of Geological and Geophysical Surveys. The observatory was formed in response to the 1986 eruption of Mount Augustine.

The observatory has a variety of tools to predict eruptions. As magma moves beneath a volcano before an eruption, it generates earthquakes, swells the surface of a mountain and sends out gases. The observatory samples gases, measures earthquake activity and watches for landscape deformities.

"Generally the earthquakes that are occurring at these volcanoes are too small to be felt unless you're standing right on the volcano," Power said.

He declined Monday to answer whether it was a good use of federal money to monitor volcano activity.

In a 1989 eruption, Redoubt sent ash high into the atmosphere and a KLM jet 150 miles away flew into the cloud. It's four engines quit and the jet with 231 passengers on board dropped more than 2 miles before the crew was able to restart all engines and land safely in Anchorage.

Scientists with the volcano observatory last fall noted an increase in seismic activity at the mountain and in January warned that an eruption was imminent. The warning level has been lowered and raised since then as the mountain cooled and heated up.

The first explosion occurred at 10:38 p.m. Sunday night and the last was at 4:30 a.m. Monday.

Alaska Airlines on Monday canceled 19 flights because of the ash clouds. In-state carrier Era Aviation canceled four, and Elmendorf Air Force Base in Anchorage kept 60 planes, including fighter jets, cargo aircraft and a 747 commercial plane, in shelters.

Winds blew the ash north toward Willow and Talkeetna near Mount McKinley, North America's largest mountain.

Volcanic ash has been used as an industrial abrasive and can injure skin, eyes and breathing passages. The far greater danger in Alaska, Power said, is to aircraft.

"Aircraft and ash really don't mix," he said. "It's the principal hazard that you see in Alaska. You can imagine flying an airplane into a sand blaster. That's what happens an airplane encounters an ash cloud."

The observatory works closely with the National Weather Service and the Federal Aviation Administration to alert pilots and airlines to the danger of ash.

Ash is angular and sharp, not like the material found at the bottom of a wood stove after a log is burned.

"It really is ground up rock," Power said. "It's more like sand."

Alaska volcanos near population centers -- Redoubt, Augustine and Spur -- tend to erupt in explosive events and it has to do with the chemical composition of the magma, Power said. The magma has a lot of silica in it and is viscous.

"Because the magma is so viscous, or sticky, the gas can't escape very easily," he said. "And so it goes ka-blam-o. It builds up a whole lot of pressure and then explodes violently. As opposed to, you go to Hawaii, or you go to other volcanoes further out the (Aleutian) Chain, where the magma is much runnier. You see those things in Hawaii where it's venting and bubbling out, it makes these beautiful flows that flow red at night."

Instead of oozing out and flowing down the mountain, magma that doesn't explode into the atmosphere will ooze into a dome in a crater that forms from the explosion.

"It can't run away," Power said. "It's like toothpaste as opposed to water."

The explosions Sunday and Monday damaged three seismometers, including the one closest to the summit. They could have been hit by flying rock or their electronic circuitry could have been damaged by lighting that often accompanies an ash plume.

"The thing is very hot," Power said. "It's rising up. It gets this big convective cell going. It's much like a thunder storm. Inside of there, there's all kinds of lightning going on."

Seven others seismometers continue to take readings on the mountain.

If Redoubt follows historic trends, there will be more eruptions in the next 48 hours, or in weeks to come.

During the 1989-1990 eruptions, ash clouds were generated on and off for about a week. Redoubt then alternated between growing a lava dome and sending up ash clouds for about five months, Power said.

"I would be surprised if we don't see more," Power said.

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