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Science for Volcano Hazards

As we are currently seeing at Bárðarbunga in Iceland, volcanoes can show signs of unrest hours, days, and months before they erupt. When the violent energy of a volcano is unleashed, the results can be catastrophic.

Photograph of the 2010 eruption of Iceland's Eyjafjallajökull volcano. Photo Credit: Icelandic Meteorological Office

Photograph of the 2010 eruption of Iceland’s Eyjafjallajökull volcano. Photo Credit: Icelandic Meteorological Office

Lava flows, debris avalanches, and explosive blasts have devastated communities. Noxious volcanic gas emissions have caused widespread lung problems. Airborne ash clouds from explosive eruptions have caused millions of dollars in direct damage, including causing engines to shut down in flight.

Risks posed by volcanic eruptions can even extend beyond the immediate vicinity of the volcano, and this is a concern in Iceland. For example, the 2010 eruption of Iceland’s Eyjafjallajökull volcano spewed an ash plume that drifted over Europe, causing the closure of large portions of the air space and resulting in an estimated $5 billion impact to world GDP.

For the latest information regarding Bárðarbunga activity, see the Icelandic Meteorological Office website.

In the United States, the U.S. Geological Survey (USGS) is the agency responsible for monitoring the nation’s volcanoes.

Starting with science is essential to keeping communities safe.

169 Active Volcanoes in the U.S.

The United States has approximately 169 active volcanoes, and more than half of them could erupt explosively. The USGS strives to improve our global understanding of how volcanoes work and how to live safely with volcanic eruptions, ultimately reducing economic and social costs.

The USGS monitors volcanoes across the nation so that the public knows when unrest begins and what hazards can be expected. The USGS issues warnings and alerts of potential volcanic hazards—including ash fall—to responsible emergency-management authorities and those potentially affected. Specific to reducing the risk to aviation from drifting ash clouds, the USGS works closely with the National Weather Service, the National Oceanic and Atmospheric Administration, and the Federal Aviation Administration. To enable the public to make informed decisions, the USGS also provides information tools, including hazard assessments, scenarios, and public information materials.

The USGS Volcano Hazards Program operates a total of five volcano observatories in cooperation with universities and state agencies. They are the Hawaiian Volcano Observatory, Cascades Volcano Observatory, Yellowstone Volcano Observatory, California Volcano Observatory, and Alaska Volcano Observatory. USGS also monitors and reports on volcanoes in the northern Marianas Islands.

National Volcano Early Warning System

The USGS National Volcano Early Warning System (NVEWS) is designed to detect precursors and signs of volcanic unrest prior to an eruption. NVEWS is a proposed national-scale plan to ensure that volcanoes are monitored at appropriate levels given their associated threats.

Currently, many volcanoes across the nation have insufficient monitoring systems, and others have outdated equipment. The NVEWS plan ensures that the most hazardous volcanoes would be properly monitored well in advance of the onset of activity, making it possible for scientists to improve the timeliness and accuracy of hazard forecasts and for citizens to take proper action and to reduce risk. 

Watch a Video & Meet Our Scientists

Watch a 6 minute video about volcano hazards and USGS science underway.


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Page Last Modified: February 2, 2011