Photo courtesy of Elizabeth Westby
Living among the grand landscapes of the Pacific Northwest, it can be easy to forget that some natural features are potentially hazardous – until it’s too late.
Eighteen volcanoes in the U.S., including Mount Baker in Bellingham’s backyard, have been classified by a recent United States Geological Survey as a “very high threat.”
States along the West Coast have 11 of the 18 volcanoes sorted into the highest threat level category by the five-tiered ranking system. The ranking system sorts volcanoes that require relatively low surveillance to those that display signs of high alarm, according to the USGS.
Though the results from the survey may appear to be reason enough to pack your bags and get out of Whatcom County, consider what geologist Elizabeth Westby from the Cascades Volcano Observatory said about the recent report.
“The assessment isn’t a list of which volcanoes are most likely to erupt, nor is it a ranking of the most active volcanoes,” Westby said. “Instead, the assessment is a quantification of the relative threat posed by the volcanoes in the United States.”
Westby also clarified that the threat ranking is meant to give geologists a better understanding of which volcanoes should be more closely monitored and what areas need more support in preparation for a potentially dangerous volcanic eruption, not to instill fear in people.
Comprehensive threat scores are assigned to the 161 young active volcanoes in the U.S. through a combination of factors. Associate professor of geology at Western Pete Stelling said geologists look at volcanic type, hazardous potential, recent activity, how often eruptions occur and the possibility of air traffic disruption. They also take into account any indications of seismic activity, the number of people an eruption could affect and history of past evacuations.
Western geology professor Jackie Caplan-Auerbach said there are many factors that have made Mount Baker the subject of renewed concern among the scientific community.
She said while the likelihood of a violent explosion remains low, because the volcano is close to communities in western Whatcom County, while the volcano remains active, it poses a significant danger to people living around it.
“Knowing when a volcano is acting up requires first knowing its normal behavior, which means we should be collecting background data now in order to identify changes, if any occur,” Caplan-Auerbach said.
According to Caplan-Auerbach, Mount Baker only has two seismometers, devices that monitor volcanic activity and are the first line of defense in the event of an eruption. She said she advocates to increase the number of devices installed on the mountain to gather data, even though deploying monitoring instruments can be challenging within a wilderness region like Mount Baker for the Cascades Volcano Observatory.
Whether given 24-hours notice or several months, Stelling said the problem lies in trying to calculate the time frame an eruption could occur, since no one actually can.
“Trying to predict an eruption is like trying to predict when you might catch an illness,” Stelling said. “Assess the symptoms and take appropriate action according to your observations.”
To interpret warning signs, Caplan-Auerbach explained how most eruptions are preceded by an increase in seismic activity. In other words, a greater number of small earthquakes and changes in magnitude detected beneath the mountain can signal a looming geologic event.
Stelling added that other symptoms worth keeping an eye on include slight inflation or swelling within the mountain, gas emissions and an increase in surface temperature on the ground within close range to Mount Baker. As these developments cannot be detected by the naked eye, satellites and other instruments are employed to collect data.
The last notable eruption occurred approximately 6,750 years ago, according to Caplan-Auerbach, who added that the majority of recent eruptions at Mount Baker have been comparatively small. She said in the future, she predicts future eruptions will also be small.
“In the past, [Mount Baker] has had enormous lahars [volcanic mudslides] that have flowed down the Nooksack and Skagit rivers. Since local populations are concentrated around the rivers, this has the potential to be damaging,” Caplan-Auerbach said.
For a minor eruption, Caplan-Auerbach said the ramifications would be relatively contained to the mountain itself, which could still affect recreation options and pose damage to the nearby ski area. However, there is still the potential for eruptive material or landslides to enter nearby Baker Lake, which could lead to dam failure. Downstream communities along the Skagit River could experience flooding and mudflows. Even a considerably small eruption could generate glacial melt, Caplan-Auerbach said.
Aside from the concern surrounding impending volcanic activity, landslides and lahars could occur even without a violent eruption due to melting glaciers and seismic activity. Caplan-Auerbach said the geologic evidence in sediment patterns and landforms indicates that lahars have previously flowed into the Sumas River, located just north of the border in British Columbia, Canada.
If the severity of the volcanic mudflow were substantial enough, Caplan-Auerbach anticipates that sediment and other debris collected over time could have the potential to flow into Bellingham Bay and even extend toward Canada. Additionally, volcanic mudflow could migrate out of stream channels and destroy urban infrastructure, devastate communities and agriculture.
Nearly $8 billion worth of private, agricultural, commercial, governmental and natural resources could be at risk from lahars and ashfall, according to estimates from the Division of Emergency Management in Whatcom County.
For folks living in western Whatcom County or students at Western, Caplan-Auerbach said the only volcanic hazard that could reach campus would be ash from a large eruption, and that would only be the case if the winds blew in an unusual direction. Typically, the wind patterns are directed eastbound and in that case ash particles would be carried away from Bellingham.
Thankfully, the brightest minds in the local community and across national borders have joined forces to plan for necessary recourse through a simulation for the worst case scenario.
On Oct. 16., an eruption exercise at the Whatcom Unified Emergency Operations Center brought a number of government agencies and organizations together throughout the week to orchestrate a timely natural disaster response.
From staged shelter preparations by search-and-rescue teams to hospital simulations to practice admitting patients affected by volcanic mudflow or ash inhalation, each division executed their respective duties to ensure that all possible outcomes in case of an emergency were thought through.
On behalf of the USGS team, Elizabeth Westby, who attended the training exercise, said that the event aims to build relationships and establish a network of support to ensure that all parties are equipped to handle a natural disaster and the challenges that follow.