Geoscience Reference
In-Depth Information
By May 17, 10,000 earthquakes had occurred on the volcano and the north flank
had grown outward at least 450 feet to form a noticeable bulge. On May 18, fol-
lowing a magnitude 5.1 earthquake, the volcano's bulge and summit slid away in a
huge landslide that depressurized the volcano's magma system, causing a massive
eruption. Fifty-seven people perished as a result of this eruption.
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Consequences of Volcanoes
Volcanoes can be very devastating to the immediate areas surrounding the eruption
site. Lava flows and pyroclastic flows will bury, knock down, and incinerate every-
thing in their path. This can lead to the destruction of homes, businesses, utilities,
modes of transportation, and agricultural lands. The gases emitted from a volcano
can cause injury or be fatal to both humans and animals. The volcanic ash and other
tephra emitted from the volcano can also lead to both injuries and fatalities. The
lahars from volcanoes can cause dams to form in creeks, streams, and rivers, leading
to flooding. There is a myriad of cascading effects from volcanoes ranging from poor
air quality issues, to mass sheltering and feeding, and mass casualty (both human
and animal). Massive amounts of volcanic ash, tephra, vegetative debris, and damages
building and vehicles can lead to massive debris management efforts.
Preparation and Planning
If an Emergency Manager has volcanoes as one of the hazards in their community,
it is important (as with all hazards) that the public is encouraged to develop indi-
vidual and family disaster supplies kits. As part of the kit, an N95 respirator should
be included. Also, citizens and/or members of the Emergency Manager's organiza-
tion should have a plan to not only evacuate if told to do so by local officials, but
also to shelter in place. Emergency Managers should work with stakeholders in
their community to determine how the massive amounts of debris will be man-
aged, as well as how citizens will be sheltered and fed both short and long term as
required. In addition, it is a good practice to have a plan as to what roads will be
cleared and opened (if possible) first. Typically, priority is given to roads that pro-
vide ingress and egress to critical facilities such as fire and police stations, hospitals,
and utilities. Also, redundant communications plans (as with all hazards) should
be put together before an eruption to ensure the ability to communicate with both
internal and external stakeholders, including the public.
Epidemics and Pandemics
Description and History
An epidemic is defined as a disease outbreak that affects more than the expected
number of cases of disease occurring in a community or region during a given