Geoscience Reference
In-Depth Information
Preparation and Planning
As with other hazards, Emergency Managers should educate the public as to what
precautions they should take should a tsunami warning be issued. Some may also
see a receding of the ocean, exposing the coastal floor. This is a sign that a tsunami
is coming, and immediate evacuation to higher ground should take place. If an
earthquake is felt along the coast, people should be instructed to turn on a NOAA
All-Hazards to see if a tsunami warning has been issued. Whatever the signal, the
public should know to stay away from the coastline, get to high ground, and stay
away from structures that could be torn down by the tsunami. Typically, there is
not a lot of advance warning for a tsunami. Therefore, once a tsunami warning is
issued, immediate action must be taken to save lives.
The NOAA has two tsunami warning centers that it operates as part of an inter-
national tsunami warning system. The Pacific Tsunami Warning Center (PTWC)
is located in Ewa Beach, Hawaii, and issues warnings for all participating members
of the international tsunami warning system in the in the Pacific. This includes
other nations. The other tsunami warning center, the West Coast and Alaska
Tsunami Warning Center (WCATWC), is located in Palmer, Alaska. This location
issues warnings for all West Coast regions of Canada and the United States, except
for Hawaii.
Volcanoes
Description and History
Volcanoes are impressive yet violent and can be very hazardous to life and prop-
erty. Eruptions are explosive and can change the landscape for several miles
around the volcano, as well as chase people from their homes (sometimes per-
manently). The droplets of sulfuric acid that are blown into the atmosphere
can temporarily change the climate globally. Those not inhabiting the areas
immediately surrounding the volcano may not lose everything to the explo-
sion from the volcano, but their homes, modes of transportation, utilities, and
businesses can be negatively affected by the byproducts of the volcano. These
include
Ash and tephra—Dust from pulverized rock and glass resulting from the vol-
canic eruption. Ash deposited on the ground following an eruption is called
an ashfall deposit. Ash is the smallest form of tephra, which is debris emitted
into the atmosphere from an erupted volcano. Ash deposits can potentially
choke out ecosystems and, if thick enough, can collapse roofs on homes and
businesses. These can also exacerbate breathing issues for those with respi-
ratory problems and cause new respiratory problems for those who do not
protect their respiratory system. Larger forms of tephra can cause injury and
further damage several miles downwind from the volcano.
