It's touch-and-go for volcano tech
- By Aliya Sternstein
- Oct 11, 2004
Scientists studying the erratic behavior of Mount St. Helens have numerous technologies that could help predict future eruptions, but the precarious environment is proving to be a challenge.
To detect imminent eruptions, scientists are planning networks of Global Positioning System receivers to map the volcano's activity. Other tools include microphones, seismometers and cameras. But all investigations are subject to change depending on the mood of the volatile volcano.
A three-member crew is installing two GPS stations and five receivers around the volcano, as part of a program called EarthScope. A team has performed helicopter reconnaissance to scout the area for good spots, said Michael Jackson, plate boundary observatory director at Unavco Inc., a nonprofit group that promotes high-
precision geodetic and strain techniques such as GPS.
"We're working to get at least five stations installed within the next week, but we haven't gotten it approved yet," Jackson said last week.
EarthScope, a project of the National Science Foundation and the U.S. Geological Survey, was created to study shifts in the continental plates. The undertaking will measure latitude and longitude at 875 permanent GPS stations, graphing how the earth moves over time. Each receiver can measure relative distance changes of less than half of a millimeter.
Such efforts should help alert scientists to unusual activity in Mount St. Helens, but studying a volcano is no simple matter. One challenge is installing equipment.
GPS generally makes it safer for scientists, because they can drop receivers along the flanks of the volcano and then monitor them from afar. In the past, scientists have relied on leveling surveys, such as what one sees on streets, in which tripods measure specific benchmark points. Also, USGS officials have installed microphones to check for explosions, and an acoustic flow monitor, which listens for rocks flowing in liquid.
But getting the equipment in place is risky business. "We're flying right over a hot volcano," said USGS spokesman John Clemens. "It's touchy."
And once installed, the equipment is always in danger. One of the recent explosions knocked out a GPS system on the dome of the volcano.
Another challenge is transmitting information from the site back to the University of Washington.
"The Forest Service has a very narrow bandwidth connection to the outside world," said Bill Steele, coordinator of the university's Seismology Laboratory. "That's one of the problems they're struggling with [in terms of ] communications. In rural areas, we still don't have good network connectivity."
Despite those problems, more technology is on the way. Officials at the USGS Hawaiian Volcano Observatory are sending a remotely operated video camera that researchers can install on the crater rim. Field crews, meanwhile, will install additional seismometers on the flanks of the volcano and protects the existing GPS sites.
But all of this careful monitoring cannot predict the future, experts said.
"It's a little bit like forecasting the weather — it's never 100 percent," said Martin Streck, associate professor of geology at Portland State University.
To help, scientists depend on data from other volcanic eruptions in Indonesia, Japan and Russia, for instance. "All this information from other volcanoes becomes our database," Streck said. "The issue is we don't know what it's going to do tomorrow, but having seen how other volcanoes behave helps us in predictions."
But sometimes, luck surmounts science. Just by chance, NASA scientists took infrared digital images of Mount St. Helens the day before it erupted. The images revealed signs of heat below the surface. Originally intended to define the limits of the lava flows from the 1980 eruption, the images may provide valuable clues about how the volcano erupted this time.
"It was an operation that we had on the calendar for some time," said Bruce Coffland, a member of the Airborne Sensor Facility at Ames Research Center, Calif.
Scientists plan to take more infrared images of the volcano this week, as well.