An Assessment of Volcanic Threat and Monitoring Capabilities in the United States: Framework for a National Volcano Early Warning System

Open-File Report 2005-1164
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Executive Summary

NVEWS – a National Volcano Early Warning System – is being formulated by the Consortium of U.S. Volcano Observatories (CUSVO) to establish a proactive, fully integrated, national-scale monitoring effort that ensures the most threatening volcanoes in the United States are properly monitored in advance of the onset of unrest and at levels commensurate with the threats posed. Volcanic threat is the combination of hazards (the destructive natural phenomena produced by a volcano) and exposure (people and property at risk from the hazards).

The United States has abundant volcanoes, and over the past 25 years the Nation has experienced a diverse range of the destructive phenomena that volcanoes can produce. Hazardous volcanic activity will continue to occur, and – because of increasing population, increasing development, and expanding national and international air traffic over volcanic regions – the exposure of human life and enterprise to volcano hazards is increasing. Fortunately, volcanoes exhibit precursory unrest that if detected and analyzed in time allows eruptions to be anticipated and communities at risk to be forewarned with reliable information in sufficient time to implement response plans and mitigation measures.

In the 25 years since the cataclysmic eruption of Mount St. Helens, scientific and technological advances in volcanology have been used to develop and test models of volcanic behavior and to make reliable forecasts of expected activity a reality. Until now, these technologies and methods have been applied on an ad hoc basis to volcanoes showing signs of activity. However, waiting to deploy a robust, modern monitoring effort until a hazardous volcano awakens and an unrest crisis begins is socially and scientifically unsatisfactory because it forces scientists, civil authorities, citizens, and businesses into “playing catch up” with the volcano, trying to get instruments and civil-defense measures in place before the unrest escalates and the situation worsens. Inevitably, this manner of response results in our missing crucial early stages of the volcanic unrest and hampers our ability to accurately forecast events. Restless volcanoes do not always progress to eruption; nevertheless, monitoring is necessary in such cases to minimize either over-reacting, which costs money, or under-reacting, which may cost lives.

Volcano monitoring in the U.S. is conducted by five volcano observatories, supported primarily by the USGS Volcano Hazards Program. Under the Stafford Act, the USGS is responsible for issuing timely warnings of potential volcanic disasters to the affected populace and civil authorities. To make maximum use of the Nation’s scientific resources, the USGS operates the observatories with the help of universities and other governmental agencies, through formal partnerships. At present, about half of the most threatening U.S. volcanoes are monitored at a basic level with real-time sensors (primarily seismic arrays), and a few are well monitored with a suite of modern instrument types and methods. However, monitoring capabilities at many hazardous volcanoes are known to be sparse or antiquated, and some hazardous volcanoes have no ground-based monitoring whatsoever.

Suggested Citation

Ewert, J.W., Guffanti, Marianne, and Murray, T.L., 2005, An assessment of volcanic threat and monitoring capabilities in the United States: Framework for a National Volcano Early Warning System: U.S. Geological Survey Open-File Report 2005-1164, 62 p.

ISSN: 2331-1258 (online)

Study Area

Table of Contents

  • Executive Summary
  • Introduction
  • Volcanic Threat Assessment: Analysis of Hazard and Risk Factors
  • Gap Analysis for a National Volcanic Early Warning System
  • Implementation Framework
  • References Cited
  • Appendices
Publication type Report
Publication Subtype USGS Numbered Series
Title An assessment of volcanic threat and monitoring capabilities in the United States: Framework for a National Volcano Early Warning System
Series title Open-File Report
Series number 2005-1164
DOI 10.3133/ofr20051164
Year Published 2005
Language English
Publisher U.S. Geological Survey
Publisher location Reston, VA
Contributing office(s) Volcano Hazards Program
Description 62 p.
Country United States
Other Geospatial Marianas Islands
Google Analytic Metrics Metrics page
Additional publication details