Tungurahua, one of Ecuador’s dozens of volcanoes, erupted August 17, 2006, killing five people and leaving thousands homeless. Photo by Adam Stinton; ©2007 Endeavors; click to enlarge.
Jonathan vs. the Volcano
by Margarite Nathe
Jonathan Lees holds a fond place in his heart for the smell of rotten eggs. “I crave that smell,” he says. It means that he’s close to the action.
Since 2002, Lees and his research team have monitored the pulse of Tungurahua — one of Ecuador’s many volcanoes and one of the most active in the world. “Every day there’s a tiny puff,” he says.
Its eruption on August 17, 2006 — much more massive than the daily puff — left five people dead and five thousand displaced. The other side of the volcano, where the popular tourist town of Baños is wedged between the foot of Tungurahua and the Amazon Basin, was spared.
But pyroclastic flow, the major killer in volcanic eruptions, desolated farmlands and livestock. The flow consists of a cloudy mixture of hot gasses — around 750°F — that’s too dense to rise into the air. So the mixture tumbles wildly down the mountainside, picking up rocks and debris along the way. Lava flow, which creeps along at about a hundred meters a day, “is usually pretty benign because people can run out of the way,” Lees says. Pyroclastic flow travels much faster, up to a hundred kilometers an hour.
Baños, which is built atop old pyroclastic flow, got lucky this time. But Tungurahua has been active for at least the last five hundred years. Can scientists predict the next eruption?
“We never say prediction,” Lees says. That involves knowing the precise time, location, and size of an event. Forecasting, on the other hand, involves stating the probability that something will happen, and that’s the closest to prediction volcanologists can get — for now.
Lees installs a seismic station — a tiny computer chip in a bulky case. Photo by Matt Welch; click to enlarge.
A look inside
From the observatory at Tungurahua, Lees’ team of researchers haul equipment on their backs through the jungle to set up stations as close as possible to the volcano’s vent, where they record seismic and acoustic waves. And the stations talk to each other.
“Say you’re a seismic station and there’s shaking going on all the time,” Lees says. “If you’re by yourself, you don’t really know if it’s an earthquake, or a cow, or something else.” So stations send out messages to other nearby stations to find out if they also felt a shake and, if so, they all send messages down to the observatory. Lees and his team secure the stations in the ground as close to the crater as they can safely get, hope the cows don’t stomp on the equipment, and watch from the observatory as the data come in.
Lees’ specialty is using seismic waves to create a picture of what’s going on inside the volcano. “We do CAT scans, just like doctors do with brains. But when doctors do a CAT scan, they’re hitting tens of thousands of points around your head. I only have three stations at Tungurahua.” And Lees’ team can’t get too close to the crater, he says, because a single breath from below would kill them.
Instead of just three stations, Lees wants a thousand. With that many tiny computer chips chattering away, he says, “we could do things I only dream about.” In the next fifty years, researchers could image the entire inside of a volcano — all from a helicopter.
“We could throw the stations out by the hundreds,” Lees says. “If we could see everything underneath the volcano and see how the fluids are moving up, then I think we could predict pretty accurately whether an eruption was about to happen.”
Lees is working with Jet Propulsion Laboratory (JPL) at the California Institute of Technology to make his plan happen. JPL developed the Mars Seismometer, a station used to track seismic activity on Mars in the same way that Lees has in mind for Earth. If the Mars Seismometer is dropped to the surface and hits something hard, it emits gluey foam that connects it safely to the surface and ensures that it will vibrate during seismic activity rather than flop around uselessly; if it hits something soft, the station bores in and is stable. Lees plans to develop the software that will bring data from the stations straight to the lab’s computers. With equipment like this, he says, scientists wouldn’t have to go into dangerous areas at all. “You would just drop it from the helicopter and get the hell out of there.”
Jonathan Lees is a professor of geophysics. Mario Ruiz, an Ecuadorian doctoral student on Lees’ team, is studying the explosive mechanisms in volcanoes, and plans to return to Ecuador to continue collaborations with other research institutions and to manage the observatory at Tungurahua.
