Review of the U.S. Geological Survey's Volcano Hazards Program (2000) / Chapter Skim
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3 Volcano Monitoring
3 Volcano Monitoring
Pages 51-64
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From page 51... ...
Certain monitoring methods, such as securing gas samples from fumaroles, require that scientists enter active vent areas. Other data can be collected remotely and with less risk, such as telemetered seismic and geodetic measurements or satellite-derived images or spectra.
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From page 52... ...
Done effectively, monitoring not only provides timely warnings to civil authorities of escalating hazards, but also leads to improved understanding and models of how volcanoes work. Monitoring generates baseline information against which changes in volcano behavior can be compared.
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From page 53... ...
. 9 ~ most~of~ich~were;~i~ina;more~than 600 ~miles~from thelvolcano.~Ash clouds ~ - ~ ::;~:: I: ::; : ::~ :::: : ::::: ::: can ~d~minish~vi~sibi~li~ ~ ~~nage~;~flig~ control systems ~~ax~d~cause~ engine failure.
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From page 54... ...
Finally, integrated studies of processes have provided a deeper theoretical understanding of how volcanoes work. On the negative side, the lack of new staff clearly has hindered monitoring efforts, particularly in the areas of physical volcanology, remote sensing, and gas studies.
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From page 55... ...
Geodetic techniques reveal ground surface deformation associated with the movement of magma beneath volcanoes or with the development of flank instabilities. More than half of the potentially active volcanoes in the United States have seismic stations, and instrumenting the rest is one of the stated goals of the VHP.
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From page 56... ...
Freely available data in a form that is easy to comprehend help educate the public, reduce suspicion during times of crisis, and allow non-VHP scientists with different perspectives and training to contribute to the interpretation of a volcano's status. On the other hand, unfettered access by improperly trained individuals to primary data from field instruments or remote sensing platforms could result in inaccurate interpretations, flawed policy decisions, and public panic.
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From page 57... ...
Gas Monitoring The collection of volcanic gas data is another essential monitoring tool that complements seismic and geodetic information. Changes in the permeability and fracture system of a volcano may be reflected in gas discharges before seismic or deformation instruments record magma ascent through newly established pathways (e.g., during the 1994 eruption of PopocatepetI, Mexico)
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From page 58... ...
Automated detection systems developed in the United States were installed by VDAP staff members and their Filipino collaborators, providing greater lead times for evacuations. Several types of electronic instruments can detect and monitor debris flows at active volcanoes, but none are currently foolproof.
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From page 59... ...
Satellite Remote Sensing Another VHP goal that the committee fully supports is the continued development of near real-time; remote sensing of volcanoes and their associated ash clouds in areas that are difficult to access. Most of the VHP's remote sensing work is centered at AVO, where satellite data are used to identify thermal anomalies and track eruption plumes and where inclement weather makes traditional observations of volcanoes more difficult.
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From page 60... ...
, which is expected to evolve a global perspective for natural hazard monitoring comparable to the PDC's role around the Pacific and Indian Oceans. The committee also considered the potential value to volcano monitoring of two existing remote sensing programs based outside the VHP, the Hazard Support System (HSS)
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From page 61... ...
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From page 62... ...
The classified nature of some of the data and the fact that military priorities control which observations are made mean that VHP personnel may have limited access, controlled by the Department of Defense. This adds an extra bureaucratic layer of communication and interpretation, slowing responsiveness and potentially reducing the effectiveness of the monitoring effort.
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From page 63... ...
Hawaii Volcanoes National Park provides a useful example of a flexible policy, which in part grew out of recognition by the communities situated near active volcanoes of the importance of good access for monitoring. High-leve!
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From page 64... ...
If the current situation is not reversed, the VHP may not be able to field the best instruments or maintain its traditional high standards for monitoring. These issues apply in varying degrees to all of the monitoring methods used by the VHP, and if they are not addressed in the near future, the program runs the risk of being unable to meet appropriate scientific goals.
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