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The scientific priorities of the Volcano Hazards Program (VHP) are defined by the fundamental questions that must be answered to fulfill the program mission of effective mitigation and useful warnings: Where are the potentially high-hazard volcanic areas? Where and in what manner is volcanic unrest occurring? Is a restless volcano going to erupt? How long and how dangerous will the eruption be? How can the potential for short- and long-term volcano hazards best be communicated?
The major programmatic activities planned in 1999-2005 to address these questions include:
In the past decade, the VHP has increased its interactions with other groups at the national level involved in volcanological research, monitoring, and mitigation. The program will continue this trend, seeking opportunities for regular coordination with agencies such as NASA, NOAA, FAA, NSF, NPS, and FEMA. Greater attention will be paid to global volcanic activity through the joint USGS/USAID Volcano Disaster Assistance Program and by closer partnership with the Smithsonian Institution's Global Volcanism Program.
The United States is a volcanically active country. In the past 200 years, more than 50 US volcanoes have erupted, many repeatedly. In this century, volcanic eruptions in Alaska, California, Hawaii, and Washington have devastated thousands of square miles of land, caused significant economic and societal disruption, and, in the worst instances, loss of life. With rising populations, development pressures, and expanding national and international air traffic over volcanic regions, the exposure of human life and enterprise to volcanic hazards is increasing.
Under the Stafford Act (Public Law 93-288), the USGS has the responsibility to issue timely warnings of potential volcanic disasters to civil authorities and affected communities. Accordingly, the mission of the VHP is to help mitigate the harmful effects of volcanic activity by assessing hazards at volcanoes and monitoring volcanic unrest, providing warning information on volcanic activity and rapidly responding to volcanic crises, conducting research to understand volcanic processes, and communicating scientific findings to authorities and the public in an effective and appropriate form. In short, the VHP mission is to prevent volcano hazards from becoming volcano disasters.
The scientific priorities of the VHP are defined by the fundamental questions that must be answered to fulfill the program mission of effective mitigation and useful warnings:
The high-priority activities to be undertaken by the VHP are both research and operational in nature.
Detection and analysis of earthquakes remain the primary tool for volcano monitoring. By the end of FY 1998, slightly more than half of the potentially active volcanoes in the US will be seismically instrumented, and achieving some level of seismic monitoring at the remaining ones is a VHP goal. Alaska has the most urgent need for additional coverage, because many Aleutian volcanoes pose a threat to aviation safety and local communities but to date have no instrumentation with which to detect unrest or eruptions.
Volcanic ash is highly hazardous to jet aircraft because it can erode compressor blades, melt onto critical engine parts, and thus cause loss of thrust power. The dangers to aviation of drifting volcanic ash are especially great in the North Pacific where many active Alaskan volcanoes are overflown daily by commercial and military aircraft on heavily traveled air routes. Kamchatkan volcanoes are an additional concern because ash clouds produced by eruptions there commonly drift into US airspace. Since 1996, with $8 M secured through the Federal Aviation Administration (FAA), the Alaska Volcano Observatory (AVO) has expanded its seismic-monitoring capabilities beyond the Cook Inlet region to include many Aleutian volcanoes. AVO's role in mitigating the threat to aircraft from volcanic ash clouds by providing timely eruption reports and forecasts to the FAA, National Weather Service, and the aviation industry is among the most important activities of the VHP. Accordingly, a priority for the VHP is to continue to expand AVO's monitoring capabilities to include more Aleutian volcanoes currently not instrumented with seismic networks. However, should FAA funding to AVO be curtailed after 1999, even maintenance of current seismic networks in the Aleutians would be impossible for the VHP without crippling redirection of funds from other observatories and research projects.
In addition to increasing the number of seismically monitored volcanoes, the VHP will augment some existing networks and enhance instrument sensitivity. Some recent eruptions have shown that precursory seismic activity can be too weak to be reliably detected and located by existing networks. Additional short-period instruments will be installed to enhance sensitivity. Broadband seismometers will be incorporated into existing networks at Long Valley and Mauna Loa and into the mobile monitoring system used for domestic and international responses. Unlike short-period instruments, broadband seismometers record waveform data that can be used to improve interpretation of the varied signals indicative of processes driving volcanic unrest. Improved seismic monitoring also requires that the VHP quickly migrate to a new data acquisition and analysis system that incorporates the USGS "Earthworm" software.
To implement these objectives, the VHP will continue to work with its university cooperators funded by the USGS to operate seismic networks in Washington and Oregon (University of Washington), Alaska (University of Alaska Fairbanks) and Yellowstone National Park (University of Utah). A new cooperative agreement with the University of Hawaii Hilo is being instituted with additional Congressional funding in FY 99.
Geodetic techniques are used to track ground-surface deformation associated with movement of magma and/or hydrothermal fluids beneath volcanoes or with development of flank instability. The VHP plans to augment established networks with new-generation, continuously recording instruments that can improve real-time forecasting capabilities. The use of permanent GPS receivers, borehole tiltmeters, and strain meters will be expanded, particularly in Hawaii and Long Valley.
In addition, the capability to access and process data collected by interferometric synthetic aperture radar (InSAR) will be further developed and tested at selected volcanoes. Many groups besides the VHP are investigating applications of this satellite-based technique, which uses multiple radar images to remotely map patterns of ground deformation with high spatial precision but spotty temporal coverage. For the VHP, InSAR primarily will be applied in a phased manner to augment existing deformation monitoring at restless volcanoes such as Yellowstone, Augustine, and Mount St. Helens and to gather deformation snapshots (baselines) at selected volcanic centers with little current deformation monitoring.
Changes in volcanic-gas flux and composition furnish important signals in identifying the existence of subsurface magma reservoirs and assessing eruption potential. The VHP plans to increasingly support efforts to improve airborne and continuous ground-based techniques for quantifying gas emissions (e.g., CO2/SO2 ratios) at restless volcanoes, as well as look for ways to better integrate seismic and geodetic monitoring with gas measurements.
In addition to serving as a measurable precursor, the presence of volcanic gases in high concentrations also poses a potential health threat to humans and livestock (e.g., volcanic smog from Kilauea's sulfur dioxide emissions and flux of carbon dioxide from soils near Long Valley caldera). Accordingly, the VHP also will continue to collect data needed to assess the environmental and health effects of volcanic gases.
Coupling Between Seismicity, Deformation and Degassing:Combined monitoring of seismicity, deformation, and gaseous emissions frequently is used to track volcanic unrest. However, interpretations linking seismic waveforms, deformation patterns, gas fluxes and the processes that cause them are incomplete. Within the VHP, priority topics of investigation include: the relationship of low-frequency (long-period) earthquakes to magma intrusion and degassing; tremor as a predictive tool; the influence of hydrothermal systems on how volcanic unrest is expressed; regional tectonic control of seismic swarms and magmatic intrusion, and innovative methods of modeling magmatic intrusion to observed strain.
AVO, with its many high-risk and hard-to-reach volcanoes, will remain the center of satellite-based remote monitoring within the VHP. AVO will continue its development of near-real time remote sensing of difficult-access volcanoes and associated volcanic ash clouds using data from civilian meteorological satellites. The VHP's remote-sensing effort could benefit from new sensors, such as those of Landsat 7 and NASA's EOS program, that can delineate lava flows, domes and other thermal features in greater detail. However, the utility of such sensors is diminished because — unlike AVHRR from meteorological satellites — the data currently are not expected to be available to AVO in real/near-real time. For effective volcano monitoring, direct reception and processing of a full complement of satellite data at AVO is necessary.
With two-year funding from the Department of Defense, the National Mapping Division of the USGS is developing and testing a new system to use classified remote imagery for world-wide eruption detection and ash-cloud tracking. VHP scientists are participating in an interagency feasibility study to evaluate system performance and establish protocols for information dissemination, provided the system has demonstrated utility.
The VHP is developing a pilot detection system that uses acoustic flow monitors and seismic instruments to automatically detect the occurrence of debris avalanches and advancing lahars. In close collaboration with Pierce County Department of Emergency Management, the pilot system targets Mount Rainier in Washington, where large lahars have the potential to quickly inundate cities and towns containing many thousands of people. The results of this pilot project will be evaluated for establishment of a permanent lahar-notification system at Mount Rainier to be operated over the long-term by local jurisdictions. Further development, deployment, and evaluation of mass-movement and flow-detection technologies will be carried out.
Another type of automated event-detection system involves single-channel seismic sensors, pressure-transient counters, and/or lightning detectors transmitting data via low-baud GOES satellites in order to identify eruptive onset in places where network coverage or visual confirmation is limited or impractical. Over the next five years, the VHP plans to improve and field test such remote eruption-detection stations for possible deployment in the Western Aleutians and the Cascades. In the future, commercial development of low-earth-orbit satellite networks for the growing cellular telephone market may provide a broadband, high-baud alternative to GOES data transmission.
Unrest at a volcanic system requires an immediate communication response to inform the public and public officials of the nature of the activity and the potential hazards. The communications response continues at least as long as the unrest does. The VHP will continue to provide scientifically authoritative "crisis communication" to people in areas of potential risk through its system of observatories. The outreach activity described in a following section is an extension of this effort.
Protocols for communication and interaction with other agencies are best established prior to any volcanic crisis. The VHP has prepared or nearly completed response and notification plans for seven individual Cascade volcanoes, the Island of Hawaii, and Alaska for volcanic-ash clouds. A priority for the VHP is to revise outdated plans and formalize additional ones, with emphasis on plans for volcanic centers in California and a Pacific Northwest volcanic-ash warning plan.
Through the Volcano Disaster Assistance Program (VDAP), a joint effort with the Office of Foreign Disaster Assistance of the US Agency for International Development, the VHP operates the world's only volcano response team capable of deploying experienced volcanologists with a portable cache of monitoring equipment within hours to days of a crisis occurring in the US or abroad. Since its inception following the 1985 eruption of Colombia's Nevado del Ruiz, VDAP has responded to more than two dozen domestic and international volcano-related emergencies. Beyond the main benefit of helping people and communities threatened by volcanic hazards, the international responses are consistent with US foreign-policy objectives abroad and enhance volcano-risk mitigation domestically by providing opportunities to learn from diverse eruptive scenarios and test new monitoring techniques. Given VDAP's programmatic importance, the VHP seeks to approximately double the size of VDAP with additional funding and specialized staffing. This goal, however, is not attainable within the current VHP budget.
The VHP also plans greater interaction with the Smithsonian Institution's Global Volcanism Project, strengthening the SI's timeliness and the VHP's geographic scope with respect to hazard awareness and information dissemination.
A priority activity for the VHP is to prepare hazard assessments and hazard-zonation maps for all monitored volcanoes based on comprehensive understanding of the geologic record of past activity at each volcano. Information on the magnitudes, styles, patterns, and frequencies of past eruptions, edifice collapses, and lahars are the basis for hazard assessments and zonation maps. This critical information is gained by thorough geologic mapping of volcanic centers and by topical field studies of specific volcanic and mass-flow deposits, both supported by high precision geochronology. Hazard assessments are not static documents; rather, they are updated and modified as new data and understanding are acquired. Basic field studies are underway or completed at most volcanic centers in the conterminous United States; Glacier Peak in Washington, the Bend/Three Sisters of Oregon, and Haleakala volcano on the Island of Maui are understudied centers for which the VHP plans additional new work. Information on eruptive histories is scanty for numerous volcanoes on the Alaskan Peninsula and in the Aleutian Islands, and VHP plans call for geologic field studies to be done in concert with installation of seismic networks.
As data accrue on frequencies and patterns of past events, probabilistic analysis of long-term future hazards becomes increasingly applicable. Also important is estimating short-term conditional probabilities of future behavior of a particular volcano during periods of unrest. The VHP will pursue both lines of analysis, engaging in probabilistic studies of eruption-recurrence intervals, lava-flow and lahar inundation, and decision-tree analysis.
Volcanoes are inherently unstable — they may be built across active faults, have steep edifices, contain unconsolidated layers, or be weakened by hydrothermal alteration. VHP priorities for assessment of the hazards of edifice instability are centered on investigating mechanisms of flank collapse (particularly in the apparent absence of a triggering eruption or intrusion), determining how lahars are generated from flank collapses and debris avalanches, and estimating volumes, sites, and likelihood of future such events.
Post-eruption high-sediment yields can lead to flooding and significant river-bed aggradation for hundreds of kilometers downstream from volcanoes. Accelerated sedimentation can persist for decades and result in fatalities and property losses. Studies primarily at Mount St. Helens will determine processes responsible for sediment remobilization, high run-off rates, and temporal variations in sediment yields and bed aggradation levels.
The VHP is using GIS technology not only to facilitate production of geologic and hazard-zonation maps, but also to begin to make accessible more of the diverse data collected by the program during volcano monitoring and research. A high priority of the VHP is to make substantial progress in creating an electronic geospatial database for use as a research tool and scientific-outreach vehicle. The database will allow diverse, cartographically based data sets and products (e.g., seismic and geodetic data from monitoring networks, hazard-assessment maps, geologic maps, geochronological data and eruptive histories, geophysical surveys, remote-sensing imagery, digital orthophoto quads, DEMs, jurisdictional boundaries, population data) to be easily accessed, combined, and queried. Existing computer hardware and software systems for data delivery and analysis can be used by the VHP, with creation of appropriate digital content for the database being the crucial responsibility of the VHP.
The VHP communicates with public officials, educators, media, and the public through fact sheets, websites, videos, workshops, presentations, field trips, teachers guides, exhibits, press releases, and cooperative outreach programs. Most efforts have focused on Kilauea, Mount Rainier, Mount St. Helens, and Long Valley. While these areas will continue to receive attention, the VHP intends to increase the amount of products and information available on other individual hazardous volcanoes (e.g., Mauna Loa), as well as produce hazard-specific information packets (e.g., on ash fall). In addition, general information on active and potentially active US volcanoes will be presented in a coherent and uniform manner through websites at the Program, Division, or Bureau level, as appropriate.
Studies of the generation, physicochemical evolution, and transport of magma through the crust to the Earth's surface comprise important research topics for the VHP. Future studies of magmatic processes should focus more explicitly on relating the course of magmatic evolution at a given volcanic center to its long-term eruption potential and on characterizing the magmatic processes that immediately precede eruption in order to improve short-term eruption forecasts. A combination of field, laboratory, and theoretical studies will be required to better understand the interplay between the various magmatic and hydrologic factors (e.g., magma supply and ascent rate, volatile content, ground-water heating) that control the explosivity and size of eruptions. In addition, syn- and post-eruptive surficial processes such as melting of snow and ice by hot eruptive products require investigation as they can be important controls on resulting hazards.
With the cuts in geothermal funding of FY 1996-97, VHP studies of hydrothermal systems are becoming more focused on the interaction of magmatic and hydrothermal fluids in active volcanic systems and less on geothermal-energy reservoirs. Such studies are significant in understanding shallow, sub-volcanic perturbations caused by pre-eruptive intrusion. With supplementary outside funding, the VHP will continue to aid other federal agencies (e.g., DOE, BLM, USFS, USAID) that are interested in the potential of volcano-hosted geothermal systems for energy production.
VHP products include such non-traditional products as state-of-the-art monitoring equipment and network arrays, emergency protocols, and web sites. In more traditional scientific venues, VHP produces geologic maps, hazard-zonation maps, hazard-assessment reports, and peer- reviewed professional articles. Information is provided to the public and media through general-interest booklets, hazard-awareness videos, fact sheets, workshops, exhibits, lectures, press releases, newspaper articles, field trips, and teachers' guides. In the coming years, VHP will continue to expand its product formats to take advantage of expanding digital technologies and Internet services and to create readily accessible sophisticated GIS databases.
Specific high-priority products for FY 1999-2005 include:
To conduct its priority activities, the VHP will need to fill critical gaps in staff expertise, primarily at the volcano observatories, which will remain the major foci for programmatic activities. The highest priority needs within Geologic Division are in remote-sensing geophysics, volcano seismology, physical volcanology, systems engineering, geodesy, and gas geochemistry. Associated support positions in geophysics, geochemistry, and GIS also are needed. A key facility and current expertise that needs to be maintained is high-precision Ar-Ar geochronology. If level-funded in the coming years, the VHP will have to confront the difficult financial conflict between the costs of hiring needed expertise and the costs associated with operating expenses and monitoring-equipment investments.
The complex natural phenomena called volcanoes require strongly multi-disciplinary methods of investigation, and, accordingly, the VHP has a long tradition of applying diverse scientific/technical specialties to meet its research and monitoring objectives. The VHP will build on this strength by better integrating its activities with other groups both within and outside the USGS.
Within the USGS:The component of the VHP that investigates volcano-hydrologic processes and mass-flow hazards such as lahars is conducted primarily with the Water Resources Division; closer inter-Divisional coordination is needed with the Geologic Division’s Landslide Hazards Program on joint interests in real-time monitoring of mass-flow events. Ties with National Mapping Division currently are being built around mutual research interest in InSAR studies. Further cooperation with Eros Data Center could be productive concerning Landsat imagery for baseline documentation of landforms at hazardous volcanoes and acquisition of digital contour data for hazard assessments. The VHP will improve its interaction with NMD’s Advanced Systems Center by assigning a volcanologist in Reston to help develop and test methods of applying classified imagery to volcano and other hazard monitoring. The opportunity exists for exchange of expertise on information technology between the VHP and the Center for Integration of Natural Disaster Information, organizationally located within National Mapping Division.
In Academia:
Provisional timeline of
selected high-priority activities of the VHP
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