Lava fountain erupts amid lush vegetation.
The string of 2018 eruptions at Kīlauea Volcano in Hawaii resulted in about $800 million in damages but no loss of life. Credit: USGS

Early in the morning on 17 May 2018, Hawaii’s Kīlauea Volcano unleashed a torrent of ash more than 3,000 meters into the sky. The explosion was just one noteworthy event in a months-long series of eruptions that destroyed more than 700 homes and caused $800 million in damage. Remarkably—thanks in large part to the relentless monitoring efforts of scientists at the Hawaiian Volcano Observatory (HVO)—no one died as a result of the destructive eruption sequence, which lasted into August.

Across the country, in Washington, D.C., Senate lawmakers happened to meet that same day to vote on a topical piece of legislation: Senate bill 346 (S.346), the National Volcano Early Warning and Monitoring System Act. The Senate passed the bill by unanimous consent, marking a big step forward for a piece of legislation more than a decade in the making.

The 1980 eruption of Mount St. Helens in Washington was the most destructive volcanic eruption in U.S. history, responsible for the deaths of 57 people and $1.1 billion in damage. Credit: Austin S. Post, USGS

The bill sought to strengthen existing volcano monitoring systems and unify them into a single system, called the National Volcano Early Warning System (NVEWS), to ensure that volcanoes nationwide are adequately monitored in a standardized way.

After ultimately lacking the floor time in the House necessary for a vote before the end of 2018, the bill was reintroduced as part of a larger package of natural resources–related bills at the start of the new Congress, which convened in January. The John D. Dingell, Jr. Conservation, Management, and Recreation Act (S.47) contained elements of more than 100 previously introduced bills related to public lands, natural resources, and water. This bill quickly breezed through Congress and was signed into law by President Donald J. Trump on 12 March; it’s now Public Law No. 116-9.

Although the bipartisan effort and the bill’s other contents, including an urgent reauthorization of the recently expired Land and Water Conservation Fund, captured the media’s attention, Section 5001, National Volcano Early Warning and Monitoring System, will have lasting effects on the nation’s volcano hazard awareness and preparation.

Volcano Observatories

Only five U.S. volcano observatories monitor the majority of U.S. volcanoes, with support from the U.S. Geological Survey’s (USGS) Volcano Hazards Program and independent universities and institutions. These observatories are the Alaska Volcano Observatory in Fairbanks; the California Volcano Observatory in Menlo Park; the Cascades Volcano Observatory in Vancouver, Wash.; HVO; and the Yellowstone Volcano Observatory in Yellowstone National Park, Wyo.

Volcanologists at these observatories monitor localized earthquakes, ground movement, gas emissions, rock and water chemistry, and remote satellite data to predict when and where volcanic eruptions will happen, ideally providing enough time to alert the local populace to prepare accordingly.

“Unlike many other natural disasters…volcanic eruptions can be predicted well in advance of their occurrence if adequate in-ground instrumentation is in place.”

The USGS has identified 161 geologically active volcanoes in 12 U.S. states as well as in American Samoa and the Northern Mariana Islands. More than one third of these active volcanoes are classified by the USGS as having either “very high” or “high” threat on the basis of their hazard potential and proximity to nearby people and property.

Many of these volcanoes have monitoring systems that are insufficient to provide reliable warnings of potential eruptive activity, whereas at others, the monitoring equipment is obsolete. A 2005 USGS assessment identified 58 volcanoes nationwide as being undermonitored.

“Unlike many other natural disasters…volcanic eruptions can be predicted well in advance of their occurrence if adequate in-ground instrumentation is in place that allows earliest detection of unrest, providing the time needed to mitigate the worst of their effects,” said David Applegate, USGS associate director for natural hazards, in a statement before a House subcommittee hearing in November 2017.

During the 2018 Kīlauea eruption, HVO, the oldest of the five observatories, closely monitored the volcano and issued routine safety warnings. However, many volcanoes lack the monitoring equipment or attention given to Kīlauea. Of the 18 volcanoes identified in the USGS report as “very high threat,” Kīlauea is one of only three classified as well monitored (the other two are Mount St. Helens in Washington and Long Valley Caldera in California).

Public Law No. 116-9 aims to change that. In addition to creating the NVEWS, the law authorizes the creation of a national volcano watch office that will operate 24 hours a day, 7 days a week. The legislation also establishes an external grant system within NVEWS to support research in volcano monitoring science and technology.

More than three of every four U.S. volcanoes that have erupted in the past 200 years are in Alaska (including Mount Redoubt, above). Credit: R. Clucas, USGS

Volcanic Impacts

Since 1980, there have been 120 eruptions and 52 episodes of notable volcanic unrest at 44 U.S. volcanoes, according to the USGS Volcano Hazards Program. The cataclysmic eruption of Mount St. Helens in 1980 was the most destructive, killing 57 people and causing $1.1 billion in damage.

Although active volcanoes are concentrated in just a handful of U.S. states and territories, eruptions have the potential to pose significant security and economic threats across the nation. A 2017 report by the National Academies of Sciences, Engineering, and Medicine concluded that eruptions “can have devastating economic and social consequences, even at great distances from the volcano.”

“People think they only have to deal with the hazards in their backyard, but volcanoes will come to you.”

In 1989, for example, an eruption at Mount Redoubt in Alaska nearly caused a catastrophe. A plane en route from Amsterdam to Tokyo flew through a thick cloud of volcanic ash, causing all four engines to fail and forcing an emergency landing at Anchorage International Airport. More than 80,000 aircraft per year, carrying 30,000 passengers per day, fly over and downwind of Aleutian volcanoes on flights across the Pacific. The potential disruption to flight traffic as well as air quality issues from distant volcanoes poses serious health and economic risks for people across the United States.

“People think they only have to deal with the hazards in their backyard, but volcanoes will come to you,” says Steve McNutt, a professor of volcano seismology at the University of South Florida in Tampa.

National Volcano Early Warning and Monitoring System Act

Passage of Public Law No. 116-9 authorizes funding for the implementation of the NVEWS. The bill recommends that Congress, during the annual appropriations process, appropriate $55 million over fiscal years 2019 through 2023 to the USGS to carry out the volcano monitoring duties prescribed in the bill.

The bill was introduced by Sen. Lisa Murkowski (R-Alaska), first elected in 2002 and consistently the most steadfast champion of NVEWS legislation. Her home state of Alaska contains the most geologically active volcanoes in the country, and more than three of every four U.S. volcanoes that have erupted in the past 200 years are in Alaska. Often in concert with Alaska’s sole House representative, Don Young (R), Murkowski has introduced volcano monitoring legislation in nearly every congressional session since her election. Five bills over the past decade have stalled in committee without reaching the floor for a vote.

“Our hazards legislation has become a higher priority because we realize that monitoring systems and networks are crucial to ensuring that Americans are informed of the hazards that we face,” Murkowski said in a speech at AGU’s Fall Meeting 2018 in Washington, D.C., last December. “They help us prepare and are crucial to protecting lives and property.”

—Forrest Lewis (, Science Writer


Lewis, F. (2019), National volcano warning system gains steam, Eos, 100, Published on 23 April 2019.

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