What would happen if Mount Baker erupted?
Government scientists have classified 18 U.S. volcanoes – including Mt. Baker in Whatcom County – as “very high threat” because of what’s been happening inside them and how close they are to people.
The U.S. Geological Survey has updated its volcano threat assessments for the first time since 2005. The danger list is topped by Hawaii’s Kilauea, which has been erupting this year.
The others in the top five are Mount St. Helens and Mount Rainier in Washington, Alaska’s Redoubt Volcano and California’s Mount Shasta.
“This report may come as a surprise to many, but not to volcanologists,” said Concord University volcano expert Janine Krippner. “The USA is one of the most active countries in the world when it comes to volcanic activity,” she said, noting there have been 120 eruptions in U.S. volcanoes since 1980.
Eleven of the 18 very high threat volcanoes are in Oregon, Washington and California.
Government scientists use various factors to compute an overall threat score for each of the 161 young active volcanoes in the nation. The score is based on the type of volcano, how explosive it can be, how recently it has been active, how frequently it erupts, if there has been seismic activity, how many people live nearby, if evacuations have happened in the past and if eruptions disrupt air traffic.
They are then sorted into five threat levels, ranging from very low to very high.
Denison University volcanologist Erik Klemetti said the United States is “sorely deficient in monitoring” for many of the so-called Big 18.
Besides the top 5, the rest of the Big 18 are: Mount Hood, Three Sisters and Crater Lake in Oregon; Akutan Island, Makushin, Mount Spurr and Augustine in Alaska; Lassen and Long Valley in California; Mount Baker and Glacier Peak in Washington; and Mauna Loa in Hawaii.
“Many of the volcanoes in the Cascades of Oregon and Washington have few, if any, direct monitoring beyond one or two seismometers,” Klemetti said in an email. “Once you move down into the high and moderate threat (volcanoes), it gets even dicier.”
The USGS said a dozen volcanoes have jumped in threat level since 2005. Twenty others dropped in threat level.
Threat scores – and levels – change because of better information about the volcanoes, Klemetti said.
Among those where the threat score – but not the threat level – is higher are Alaska’s Redoubt, Mount Okmok, Akutan Island and Mount Spurr. Threat scores also rose for Oregon’s Newberry Volcano and Wyoming’s Yellowstone.
None of the Big 18 changed in overall threat levels, even though 11 had overall threat scores dropping.
At 10,781 feet Mt. Baker is the third tallest mountain in the state. It’s history was detailed in a Bellingham Herald story in 2015:
“Mount Baker is part of a field of about 20 volcanoes that arose, erupted and were worn down by glaciers over some 4 million years, says Dave Tucker, who helped start Mount Baker Volcano Research Center. The largest eruption, about 1.1 million years ago in the vicinity of today’s Mt. Baker Ski Area, rivaled the blast that created Crater Lake basin in Oregon.
“Today, a ridge of craggy peaks west of Baker is called the Black Buttes. Between 500,000 and 280,000 years ago, the Black Buttes volcano grew into a mountain considerably larger than Baker. In geological time, Baker is a baby, perhaps 40,000 years old.
“Baker’s summit, called Carmelo Crater, grew quiet about 12,000 years ago, but the mountain has kept busy. About 6,500 years ago, a major blast created Sherman Crater, just south of the summit and still the site of escaping steam and gases.
“A massive mudflow once poured down the middle fork of the Nooksack River, reaching beyond Nugent’s Corner, and magma nearly reached the surface at Sherman Crater in 1843, resulting in a large steam eruption.
“In 1975, a large quantity of muddy steam rose into the sky, turning much of the ice-filled Sherman Crater into a steaming lake. An eruption was feared, so the mountain and Baker Lake were closed for the summer.”