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What We Do - Volcano Hazards Program

The mission of the USGS Volcano Hazards Program is to enhance public safety and minimize social and economic disruption from eruptions by delivering effective forecasts, warnings, and information on volcano hazards based on a scientific understanding of volcanic processes.

USGS CVO scientist answers media inquiries relating to the increase in Mount St. Helens activity, October 2004.

The USGS Volcano Hazards Program (VHP) monitors and studies active and potentially active volcanoes, assesses their hazards, and conducts research on how volcanoes work in order for the USGS to issue "timely warnings" of potential volcanic hazards to emergency-management professionals and the public. Thus, in addition to collecting and interpreting the best possible scientific information, the program works to effectively communicate its scientific findings and volcanic activity alerts to authorities and the public.

Volcano monitoring networks and scientific observation are basis for warnings, research, and situational awareness.

Pagan Volcano is the largest and one of the most active volcanoes in the Northern Mariana Islands. Prior to 2013, the volcano was not monitored with any ground-based instruments, so activity was observed only by satellite or by the few island inhabitants. Although geographically remote, eruptions from Pagan can threaten international air traffic. A collaborative effort by the USGS, the US Army Corps of Engineers, and Southern Methodist University installed seismic network, infrasound equipment and webcams to monitor activity and provide the necessary warnings.

Data collected by volcano-monitoring networks and extensive fieldwork surveys are indispensable; they help scientists interpret volcanic behavior, forecast eruptions, identify likely eruption impacts, and provide situational awareness – information relating to eruptions and unrest. The most effective monitoring is achieved by applying a combination of techniques (seismic, geodetic, hydrological, and geochemical) via arrays of several instruments at single volcanoes on a continuous near-real-time basis. Airborne and satellite remote-sensing technology provide enhanced capabilities for detecting and tracking signs of unrest and eruption including gas emissions, topographic changes, ash clouds, and lava flows. Monitoring data feed into research studies that help scientists discriminate whether signals are eruption precursors or signify temporary fitfulness without eruption, evaluate whether a volcanic eruption is building up or calming down, and identify what factors trigger and control the style and explosivity of eruptions.

Hazard assessments are the foundation for effective hazard mitigation strategies.

Lava-flow hazard zone map, Hawai‘i Island

VHP develops both long- and short-term volcano hazards assessments. Long-term assessments are based upon detailed geologic mapping and dating a volcano's deposits, which provide the record of past eruptions. Using the knowledge of past behavior, models of potential volcanic hazards (e.g. ash plumes and ashfall, lava-flow or lahar pathways and travel times) are created. Geologic and modeling data are integrated with high-resolution topographic mapping of the landscape and analyzed using the Geographic Information System (GIS) to develop comprehensive hazard-zonation maps and assessments, which may include risk and vulnerability analysis and/or probabilistic recurrence information. These provide an essential basis for monitoring network design, long-term eruption forecasting, land-use planning, and short-term emergency planning. During an eruption, real-time monitoring, observations, and hazards models are combined to evaluate the most likely hazards on a day-to-day basis, which feed into short-term hazards assessments.

Research of volcanic processes and historic impacts provides lessons for reducing volcanic risk.

Kate Potter and Julia Griswold prepare for the next set of experiments at the debris-flow flume, located at H. J. Andrews Experimental Forest, Oregon.

VHP scientists employ many different research disciplines to investigate volcanic processes from the magma storage regions beneath volcanoes to eruption products on the surface and in the atmosphere. Geologic research provides a long-term view of volcanic behaviors and eruption intervals, which helps anticipate the most likely styles and frequency of activity in the future. Mathematical and physical models of volcanic processes help scientists interpret the data streams from volcano monitoring networks. Microscopic chemical and physical analysis of eruption products provides insight into the duration and location of magma storage and how it erupts from a volcano. Such fundamental research provides greater understanding of the physical behavior of volcanoes and how eruptions could impact communities and ecosystems. Research provides the scientific factual basis for delineating areas impacted during past eruptions, improving eruption forecasts and warnings, enabling quantitative hazard assessments, and bringing heightened awareness to volcanic risks.

VHP engages communities and the public to prepare and respond to eruptions and unrest.

Preparation is key to staying safe and experiencing minimal impact during hazardous volcanic events. For communities and infrastructure at risk, VHP personnel work directly with Federal, State, and local officials, as well as industry, news media, and the public, to increase awareness of location-specific hazards and to participate in response planning activities well ahead of volcanic crises.

A diverse group of state and federal stakeholders assembled at the California Office of Emergency Services headquarters to discuss the addition of a new Volcano Annex or addendum to California's State Emergency Plan. Volcanic eruptions occur in California about as frequently as the largest San Andreas Fault Zone earthquakes: ten eruptions have occurred in California in the last 1000 years. Recognizing the potential for renewed volcanism in California is an essential first step in mitigating hazardous impacts.

To be effective during a volcanic event, volcano-hazard information must be communicated quickly and accurately. VHP provides situational awareness by 1) issuing authoritative forecasts, warnings, and status updates of volcanic activity; 2) investigating and rectifying reports of unrest and eruption that are false or misleading; 3) providing access to volcanic information and real-time data to the public via websites, social media, and subscription services; 4) participating in targeted volcano-hazard education and planning activities.