Restless Mountain Story by Dennis Hollier
Shane Turpin cuts the throttle and lets the boat drift down on the writhing column of steam and ash. This is where the lava flows into the sea, and it’s an awesome and infernal scene. From this close, the gigantic plume seems alive, coiling and coiling upon itself as the trade winds blow it low over the steaming water. Sea witches—delicate, evanescent water spouts—undulate like tentacles from its dark underbelly. And, at its churning center, a seemingly endless succession of explosions pummel the shore with a hailstorm of scoria and splattered lava.
“That’s Madam Pele,” Turpin says, hoisting a video camera to his shoulder.
Turpin, the owner of Lava Ocean Adventures, is obsessed with lava. He likes to get close to it. He likes to smell its sulfurous fumes. Under the right circumstances, he’ll even touch it. He and his father are famous for scuba diving on the flow; in grainy YouTube footage, you can see the two of them underwater using stout gaff hooks to sculpt the livid pillows of lava. For people like Turpin, the recent lava flow has been a bonanza. Over the last several months, it’s been flowing almost continuously, pouring from the Pu‘u o‘o vent high on the flanks of Kïlauea and running down along the old Royal Garden flows and into the sea. For most of that route, it’s buried in a lava tube, a kind of natural plumbing that forms when a tongue of lava hardens on the outside but continues to flow underneath. For real lava hounds like Turpin, the place to see actual, flowing lava is here off the Big Island’s wild Puna Coast.
Probably no one has been here as much as Turpin. Several times a week, at the helm of a battered old tour boat he calls the Lava Cat, he brings small groups of visitors to view the spectacle. Today, continuous steam explosions obscure the lava. Turpin lets the boat drift in the afternoon swells just beyond range of the falling debris while we watch for a glimpse of lava in the surging plume. Suddenly, a shift in the wind parts the column of steam, and we all stare with amazement into the incandescent maw of a fresh spatter cone. It might as well be the center of the earth.
The plume of steam rising on the Puna Coast is only the smallest of three such plumes that bend in the lee of Kïlauea. For the scientists who study the volcano, this one is just an afterthought. The real activity is up the hill—at Pu‘u o‘o and especially at the Halema‘uma‘u crater at the summit of Kïlauea. A flurry of tremors and sulfurous belches that occurred during the summer of 2007 preceded the current episode in the ongoing eruption at Pu‘u o‘o. In July, the crater, which had been empty for months, filled again with lava. Then on July 21, lava began to spill from fissures in its flank. Concern grew by August as one flow meandered northeastward for the first time in more than twenty years, briefly alarming the residents of Pahoa and Hawaiian Beaches. But in November, the lava began to flow south again from a new fissure. At first it ponded. Then, on Thanksgiving eve, it broke loose and writhed its way across the landscape. In February lava flowed again in Royal Gardens, pausing to engulf some of the last remaining houses there before moving on to the sea on March 4.
March saw further trouble: A new vent opened in Halema‘uma‘u, suddenly doubling the emissions of “vog,” or volcanic fog—a toxic cloud of sulfur dioxide—into the atmosphere. Volcano National Park officials closed down large sections of the park. Warnings were issued for people with respiratory problems. Vog obscured visibility on the Kona Coast, and when the usual trade winds failed, Kona winds carried the haze as far as O‘ahu and even Kaua‘i. That steady dose of acidic gas would eventually play havoc with Big Island agriculture, devastating many of the coffee and protea flower farms of Puna, Ka‘u and South Kona. Then, on the night of March 19, Halema‘uma‘u surprised scientists when it exploded and rained debris onto the popular crater overlook trail and parking lot. For the first time in recorded history, Pu‘u o‘o and the summit were erupting at the same time.
Kïlauea is one of the world’s most active volcanoes; Pu‘u o‘o or one of the other vents along what are known as the Northeast and Southwest Rift Zones has been erupting almost continuously since 1983. But the recent activity represents a change in the volcano’s behavior: The Halema‘uma‘u eruption is the first summit eruption in nearly twenty-four years. Also, although Kïlauea is famous for its effusive eruptions—for flowing lava—Halema‘uma‘u produced a rare explosive eruption. And that’s what has scientists
own in the shadowy basement of the Hawaiian Volcano Observatory is an office littered with rocks and plastic bags containing gravel and dust and grit— the stock in trade of an old-fashioned volcanologist. Don Swanson doesn’t look like your typical scientist. He’s a slight man with a grizzle of beard and red dirt rubbed deep into the thighs of his faded jeans, but as one of the senior geologists at the observatory and an expert on Kïlauea’s explosive history, perhaps no one knows the volcano as well as Swanson.
“There’s a kind of general skeleton model for how the volcano works that I think most of us try to build on,” Swanson says. “Magma enters the volcano directly beneath the summit area. It comes up from a depth of maybe 100 kilometers; it enters some kind of magma reservoir and then is distributed from there. Magma from the reservoir can either come directly to the surface and erupt right in the caldera—into Halema‘uma‘u, for example—or it can go into one of the two rift zones.” Unfortunately, the current Halema‘uma‘u eruption presents problems for this standard model.
Swanson explains, “Our feeling always has been that to have an eruption, you have to have magma intruding into the volcano. If so, the magma reservoir is going to swell, and the ground surface is going to distend.” Last year, though, rather than swelling, the summit actually deflated. “That’s what has us all baffled,” Swanson says. “Before the Halema‘uma‘u eruption began, there was no swelling of the volcano. It was a stealth eruption. From the ground deformation perspective, there was nothing that would have anticipated that there was going to be such a big change.” And, for all their high-tech equipment, volcanologists are still flummoxed when it comes to making predictions, and Swanson won’t speculate about what might be coming next. “We have no idea,” he says.
But scientists can look to the past for precedent, and Swanson wants to put this eruption into historical context. “Kïlauea,” he says, “is usually considered a docile volcano, sort of a milquetoast. It puts out lava flows, and the lava can be destructive to property, but it isn’t very dangerous to people.” This, of course, is part of the volcano’s charm, both with scientists and tourists: You can get close to the action. “But,” he adds, “if you look very closely at the explosive record of Kïlauea—going back 2,000 years plus—you will find Kïlauea has been quite explosive. In fact, Kïlauea explodes about as often as does Mount St. Helens. The explosions, for the most part, aren’t as large as Mount St. Helens, but in the last 1,500 years, at least six of these explosions sent debris flying up into the jet stream.” For good measure, he points out, “Jet engines and volcanic ash don’t mix.”
By way of example, he says, “In 1790 there was a famous eruption that killed somewhere between about eighty and 800 people or more, depending on the estimate you choose. The botanist David Douglas estimated 5,405 people died.” In this instance it’s believed that many of the dead were the soldiers of Keoua, on their way to do battle with Kamehameha I for control of the island of Hawai‘i, so this eruption may have dramatically changed Hawaiian history. “I think they were killed by surges,” Swanson says, “clouds of hot gas and rocks that rushed at hurricane velocity from the caldera and engulfed them.”
“More recently,” he says, “in 1924 there were three weeks of explosions in Halema‘uma‘u, explosions that killed a person and did some damage. There was a mud rain in lower Puna. Back then there used to be a train then that went from Hilo to Kapoho, but it had to stop running because the tracks were too slippery.”
The long view of science gives Swanson a cautious cast. “Most of the research on Kïlauea has been focused on its effusive rather than its explosive history,” he says. “We’re just trying to bring the explosions into people’s thinking—not to panic people, because there’s no reason to panic, and not to frighten people, because there’s no reason to be frightened—but just for people to realize that Kïlauea does have a dark side. After all, the 1790 event killed more people than any other volcano in the US.”
At least for now, the mountain’s lowlevel grumbling remains a tourist attraction. In lower Puna the county has marked out a trail across old lava flows that as recently as 1990 inundated the remote village of Kalapana. Every day, thousands of people trudge from a makeshift parking lot, over the beds of ropy pahoehoe (smooth lava), out to the edge of the escarpment where the old Kalapana flow ends. From this vantage they can see where the lava flows into the sea nearly a quarter-mile away. Mostly, they see the plume as it surges out over the ocean. Sometimes they can see the Lava Cat wending back and forth beneath the column of steam and ash. But as the sun goes down, the foot of this great steam cloud begins to glow, and the fountains of lava once hidden in the steam become incendiary and beautiful against the darkening background of the sea. It’s a sight not to be missed.
