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Frequently Asked Questions » Why doesn't the Smithsonian post hazard alert levels for all volcanoes?
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Why doesn't the Smithsonian post hazard alert
levels for all volcanoes?
The assignment of official hazard alert levels is the responsibility of national or regional volcano observatories
under the umbrella of the World Organization of Volcano Observatories (WOVO). The following discussion of
volcanic hazard alert levels is adapted from the WOVO website, with permission.
Volcanic Alert Levels vary across the world
In a volcanic crisis, there is often worldwide interest in the volcano's hazard alert levels. With the exception of
color codes for aviation, though, there is currently no standardized international volcano alert levels system.
This is due to: (a) wide variation in the behavior of individual volcanoes and in monitoring capabilities, and (b)
the different needs of populations, including different languages and symbolism of colors used. National
volcano observatories have developed alert level protocols that are regionally variable and differ significantly in
detail. The WOVO site contains links to the regional volcano observatories and the alert systems they utilize.
Caution about use of Volcanic Alert Levels
Organizations with interest in natural hazards are strongly cautioned against posting global volcano hazard
alerts or eruption "forecasts" that do not originate from volcano observatories or regional agencies with both
responsibility for and familiarity with those volcanoes. Posting of hazard alert levels can have major public
safety and economic implications, and should not be done lightly. The data needed to provide alert levels come
from onsite and remote monitoring instrumentation and are best evaluated by staff of regional volcano
observatories who are the most familiar with activity at their volcanoes. The responsible observatories and
organizations are listed on the WOVO website, and readers are directed to these organizations for information
on current volcano alert levels.
Currently, there is no WOVO-endorsed source of worldwide Volcanic Alert Levels, with the exception of
aviation color codes. For those seeking a near real-time overview of current reported activity that incorporates
direct observatory sources WOVO recommends the Weekly Activity Reports compiled by the Smithsonian
Institution's Global Volcanism Program (GVP) and the U.S. Geological Survey.
Aviation Color Codes
Many instances of aircraft flying into volcanic ash clouds have demonstrated the life-threatening and costly
damages that can be sustained. Consequently, a universal volcanic alert level system for aviation has been
developed (as part of the International Airways Volcano Watch, a universal warning system coordinated by the
International Civil Aviation Organization, a UN specialist agency). This system uses four color codes, designed
to help pilots, dispatchers, and air-traffic controllers quickly find the status of numerous volcanoes that might
endanger aircraft.
The color codes reflect conditions at or near a volcano and are not intended to indicate hazards posed
downwind by drifting ash - all discernible ash clouds are assumed to be highly hazardous and to be avoided.
Furthermore, the aviation color code should not be extrapolated to represent hazards posed on the ground,
which might be quite different.
Not all observatories currently provide information in this format, but where they do, the aviation color code is
currently defined as below.
AVIATION COLOR CODES RECOMMENDED BY THE
INTERNATIONAL CIVIL AVIATION ORGANIZATION
Volcano is in normal, non-eruptive state.
or, after a change from a higher level:
GREEN
Volcanic activity considered to have ceased, and volcano reverted to its normal, noneruptive state.
Volcano is experiencing signs of elevated unrest above known background levels.
or, after a change from higher level:
YELLOW
Volcanic activity has decreased significantly but continues to be closely monitored for
possible renewed increase.
Volcano is exhibiting heightened unrest with increased likelihood of eruption.
or,
ORANGE
Volcanic eruption is underway with no or minor ash emission. [specify ash-plume height if
possible]
Eruption is forecast to be imminent with significant emission of ash into the atmosphere
likely.
RED
or,
Eruption is underway with significant emission of ash into the atmosphere. [specify ashplume height if possible]
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 Frequently Asked Questions
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o What is the world's highest volcano?
o How long does an eruption last?
o Has volcanic activity been increasing?
Why doesn't the Smithsonian post hazard alert levels for all volcanoes?
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