Volcanoes — A National Threat

When the violent energy of a volcano is unleashed, the results are often catastrophic. The risks to life, property, and infrastructure from volcanoes are escalating as more and more people live, work, play, and travel in volcanic regions.

Since 1980, 45 eruptions and 15 cases of notable volcanic unrest have occurred at 33 U.S. volcanoes.

Lava flows, debris avalanches, and explosive blasts have invaded communities, swept people to their deaths, choked major riverways, destroyed bridges, and devastated huge tracts of forest.

Noxious volcanic gas emissions have caused widespread lung problems. Airborne ash clouds have disrupted the health, lives, and businesses of hundreds of thousands of people; caused millions of dollars of aircraft damage; and nearly brought down passenger flights.

Tools for Today

The U.S. Geological Survey (USGS) is responsible for issuing timely warnings of potential volcanic disasters to affected communities and civil authorities.

USGS scientists, with State, Federal, and academic partners, operate five volcano observatories that monitor volcanic activity in Hawaii, the Cascade Range, Alaska, Long Valley in California, Yellowstone National Park, and the Northern Mariana Islands.

After 25 years of intense research on restless volcanoes in the United States and around the globe, the USGS has greatly advanced its ability to evaluate volcanic risks and hazards. In the
process, the USGS has helped save tens of thousands of lives and has developed a suite of new volcano-monitoring tools. Many of these tools allow large amounts of data to flow in realtime from remote volcanoes to observatories for analysis and interpretation.

The USGS can now better anticipate volcanic hazards in time for civil authorities, communities, and the aviation sector to take preparatory actions—but only if a volcano is adequately monitored with instrument networks in place before unrest develops.

Preparing for Tomorrow

Volcanic eruptions herald their coming over periods of days to years with detectable signals of unrest. Many human risks associated with eruptions can be drastically reduced through the use of
hazards assessments, response planning among scientists, State, and local authorities, and proper monitoring and technology.

In 2005, the USGS released the first ever comprehensive and systematic review of the 169 U.S. volcanoes. The report establishes a framework for a National Volcano Early Warning System (NVEWS). The framework calls for enhanced instrumentation and monitoring at targeted volcanoes, and a 24-7 volcano watch office to improve the ability to provide rapid, reliable hazard warnings.

The NVEWS report ranks the most dangerous U.S. volcanoes that pose a threat to human lives, property, and aviation safety and also discusses monitoring gaps at each volcano. Alaska, California, Washington State, Oregon, Hawaii, Wyoming, and the Commonwealth of the Northern Marianas have dangerous volcanoes with either significant monitoring gaps or no monitoring in place. The report can be accessed online at http://pubs.usgs.gov/of/2005/1164/.

To help keep communities safe, it is essential to monitor hazardous volcanoes so that the public knows when unrest begins and what hazards can be expected. The USGS helps the public, policymakers, and emergency managers make informed decisions on how to prepare for and react to volcano hazards and reduce losses from future volcanic eruptions and debris flows.

Information courtesy of the U.S. Geological Survey