PPA 573 – Emergency
Management and
Homeland Security
Lecture 5a – Natural, Medical, and
Technological Hazards; Risk
Assessment
Hazards: An Introduction
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Hazard:
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Risk:
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A source of danger that may or may not lead to an
emergency or disaster and is named after the emergency
or disaster that could be so precipitated.
Susceptibility to death, injury, damage, destruction,
disruption, stoppage, and so forth.”
Disaster:
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Event that demands substantial crisis response requiring
the use of government powers and resources beyond the
scope of one line agency or service.”
Hazards: An Introduction
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Hazard identification is the foundation of all
emergency management activities.
When hazards react with the human or built
environment, the risks associated with that
hazard can be assessed.
Hazards: An Introduction
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Understanding the risk posed by identified
hazards is the basis for preparedness planning
and mitigation actions.
Risk, when realized, such as in the event of an
earthquake, tornado, flood, and so on, becomes a
disaster that prompts emergency response and
recovery activities.
All emergency management activities are
predicated on the identification and assessment of
hazards and risks.
Natural Hazards - Climatic
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Floods.
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Slow or fast rising. Develop over a period of days.
Large-scale weather systems with prolonged rainfall or
onshore winds.
Also caused by locally intense thunderstorms, snowmelt,
ice jams, and dam breaks.
Flash floods have little or no warning.
Floods are the most common type of disaster, accounting
for 51 percent (61% with storm surge) of all disaster
requests to the federal government.
FEMA estimates that more than 9 million households and
$390 billion in property are at risk of flooding.
Flooding Case Study – Great
Midwestern Floods 1993
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534 counties in nine states (17% of counties in
U.S.).
Federal costs: $4.2 billion in direct federal
assistance, $1.3 billion in federal flood insurance
payments, and more than $621 million in federal
loans to individuals, businesses, and
communities.
Federal payments came from FEMA, USDA, SBA,
HUD, DOC, USACE, HHS, DOE, DOL, EPA, and
DOI.
Natural Hazards - Climatic
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Hurricanes – all hurricanes start as tropical waves
that grow in intensity and size to tropical
depressions, which in turn grow to be tropical
storms (39 to 73 mph).
Hurricanes have wind speeds in excess of 74
mph. Eye is 20 to 30 miles wide. May extend
outward 400 miles.
Hurricane season runs from June 1 to November
30. August to September are the peak months.
Most of the deaths and damages from hurricanes
arise from storm surge.
Hurricanes
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Storm and hurricane scales.
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Beaufort Scale of wind intensity.
Saffir-Simpson Hurricane Scale.
Notable hurricanes in U.S. history.
Hurricane Katrina video
Natural Disasters - Climatic
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Tornadoes.
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A tornado is a rapidly rotating vortex or funnel of air
extending groundward from a cumulonimbus cloud.
Approximately 1,000 tornadoes are spawned by
thunderstorms each year. Most remain aloft as funnel
clouds.
Tornadoes can lift and move heavy objects, destroy or
move whole buildings, and siphon large volumes of water.
Tornadoes follow the path of least resistance, making
residents of valleys most vulnerable.
Tornadoes
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Tornado Scales.
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Enhanced Fujita Tornado Scale.
Case Study: Super Outbreak, April 3-4,
1974.
Natural Disasters - Climatic
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Snow and ice storms.
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Severe winter storms consist of extreme cold and heavy
concentrations of snowfall or ice. A blizzard combines
heavy snowfall, high winds, extreme cold, and ice storms.
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NW – cyclonic weather systems from the North Pacific or
Aleutian Island region.
Midwest and Upper Plains – Canadian and Arctic cold fronts.
NE – Lake effect snowstorms.
Eastern and NE – extra-tropical cyclonic weather systems.
Northeast Snowfall Impact Scale.
Natural Disasters – Other Climatic
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Landslides or mudslides.
Droughts
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Wildfires.
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Palmer Drought Severity Index.
NNDC Climate Data Online.
Surface fire, ground fire, crown fire.
Wildland fires, interface or intermix fires, firestorms,
prescribed fires.
Extreme heat.
Natural Disasters – Other Climatic
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Coastal erosion.
Thunderstorms.
Snow avalanches.
Hailstorms.
Natural Disasters - Geological
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Earthquakes.
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An earthquake is a sudden, rapid shaking of the earth
caused by the breaking and shifting of rock beneath the
earth’s surface.
This shaking can cause buildings and bridges to collapse;
disrupt gas, electric, and phone service; and sometimes
trigger landslides, avalanches, flash floods, fires, and
tsunamis.
Buildings with foundations resting on unconsolidated
landfill, old waterways, or other unstable soil are most at
risk.
Earthquakes
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Earthquake scales.
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Richter and Modified Mercalli Scales (next slide).
Moment Magnitude Scale.
Case Study: Alaskan Earthquake 1964.
Earthquake Case Study – Alaskan
Quake 1964
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On March 27, 1964 at 5:36 p.m., south central
Alaska suffered the second largest earthquake in
recorded human history. The estimated moment
magnitude (Mw) of 9.2 (Sokolowski 2002) was
only exceeded by the Chilean earthquake of 1960
(Mw 9.5). The duration of the Alaskan quake was
approximately four minutes. By contrast, the
Northridge earthquake in 1994 (Mw 6.7) lasted
only fifteen seconds and the San Francisco
earthquake of 1906 (Mw 7.9) lasted between thirty
and forty-five seconds.
Earthquake Case Study – Alaskan
Quake 1964
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The area of serious damage extended 50,000 square miles;
the area experiencing the quake covered 1,000,000 square
miles. The affected area contained 60 percent of the state’s
population and 55 percent of the economic activity. The
number of deaths totaled 115; the estimated damages were
$311 million. The greatest structural damage occurred in
Anchorage, Alaska, seventy-five miles west of the epicenter
of the quake. Most of the deaths were the result of seismic
sea waves (tsunamis), one of which struck 2,500 miles away
in Crescent City, California.
Earthquake Case Study – Alaskan
Quake 1964
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The earthquake disrupted the normal operation of local and
state government.4 As a result, the U.S. military played a
critical role in the first response to the disaster. The military
provided emergency communications, aided power
companies in restoring service, served meals within two
hours of the quake, provided security and direct relief to the
Greater Anchorage area and virtually all of the other stricken
areas in Alaska (FRDPCA 1964). Federal civilian response
followed quickly. Alaska Governor William Egan formally
requested that President Lyndon Johnson declare a major
disaster under the Federal Disaster Act of 1950 (P.L. 81-875)
on the morning of March 28, 1964. The President granted
the request later that afternoon.
Earthquake Case Study – Alaskan
Quake 1964
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Immediately after the declaration, the Office of Emergency
Planning (OEP) assigned specific disaster response and
recovery missions to the Army Corps of Engineers; the Navy
Bureau of Yards and Docks; the Federal Aviation Agency; the
Bureau of Public Roads; the Alaska State Highway
Department; several cabinet departments (Interior, Health,
Education, and Welfare [HEW], Labor, Agriculture,
Commerce, and Treasury), and a number of independent
agencies. On June 12 OEP requested and President
Johnson allocated $17 million from the President’s Disaster
Relief Fund, which was used primarily to reimburse federal
agencies for the emergency work they performed.
Earthquake Case Study – Alaskan
Quake 1964
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Concerned about the magnitude of the disaster relative to
state resources and the absence of mechanisms to ensure
recovery, President Johnson issued Executive Order 11150
establishing the Federal Reconstruction and Development
Planning Commission (FRDPCA) on April 2, 1964. The
Commission consisted of the Secretaries of Defense, Interior,
Agriculture, Commerce, Labor, and HEW; the Director of the
Office of Emergency Planning; the Administrators of the
Federal Aviation Agency, the Housing and Home Finance
Agency, and Small Business Administration; and the
Chairman of the Federal Power Commission. U.S. Senator
Clinton P. Anderson (Democrat-New Mexico) chaired the
commission.
Earthquake Case Study – Alaskan
Quake 1964
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The Commission focused largely on five tasks:
damage analyses, soil studies, engineering
practice, price monitoring, and reconstruction
planning. The Commission supervised the
disbursement of $155 to $222 million of federal
aid to state and local governments, $87 to $110
million of federal aid to private individuals and
groups, and $82 million for restoration of federal
facilities and direct federal operations. In short,
the federal government reimbursed virtually all of
the private and public costs associated with the
disaster.
Natural Disasters - Geological
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Volcanic eruptions.
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Mountain that opens downward to a reservoir of molten
rock.
Volcanoes are built up from their own eruptive products.
Pressure from gases and molten rock cause eruptions.
Unlike other disasters, volcanoes give months of
forewarning.
Volcanoes can produce tsunamis, flash floods,
earthquakes, rock falls, and mudflows.
Volcanic Eruptions
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Volcano Explosivity Index (VEI).
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Additional link.
Mt. St. Helens video (still pictures).
Volcanic
Eruptions – Mt.
St. Helens, 1980
Case Study – Mt. St. Helens
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On March 20, 1980, a moderate earthquake of 4.1 on Richter scale
occurred under Mount St. Helens in southwestern Washington.8
Multiple microquakes of varying intensity occurred on March 21 and
22, and continued throughout the eruption period. The increasing
activity prompted seismologists and geophysicists from the U.S.
Geological Survey and the University of Washington to measure
seismic activity around the volcano. The first eruption occurred on
March 27, spitting plumes of ash and steam 10,000 feet, and
forming a 250-foot-wide crater within the preexisting summit crater.
Between March 27 and April 21, the mountain intermittently spewed
ash and steam. Visible activity temporarily ceased through the rest
of April and early May, resuming on May 7. However, seismic
activity persisted throughout the period. The movement of magma
began to create a bulge on the north face of the mountain. In effect,
Mount St. Helens was being forcibly shaken apart.
Case Study – Mt. St. Helens
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On Sunday, May 18, 1980, at twenty seconds after 8:32 a.m., a magnitude
5.1 earthquake under the mountain literally popped the cork on the
volcano. The bulge on the north flank of the mountain collapsed, creating a
debris avalanche moving laterally down the mountain at speeds ranging
between 110 and 155 mph. The sudden release of pressure unleashed an
explosion of ash, steam, rock, and hot gases that quickly overtook the
avalanche, reaching speeds of 670 mph. The explosion (estimated in
intensity at the equivalent of ten megatons) created a blast zone extending
nearly 20 miles. The vertical column of ash from the eruption reached
heights of 50,000 feet and drifted east over Washington, Idaho, and
Montana, burying some sections of Washington under a foot of ash. Hot
pyroclastic flows also streamed down the north side of the mountain.
Within hours, melted snow and glacier ice mingled with debris and
pyroclastic material to generate major mudflows down the Toutle and
Cowlitz rivers, ultimately clogging the Columbia River and dumping
material into Swift Reservoir.
Case Study – Mt. St. Helens
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Because of the unexpected lateral movement of the eruption, fifty-seven
people, including several geologists, lost their lives. Most were in areas
believed to be safe. The lateral blast also devastated about 230 squares
miles of timber north of the volcano, vaporizing the trees within five miles,
leveling them within nineteen miles, and scorching beyond that. The
mudflows caused major flooding along the Toutle and Cowlitz Rivers. “The
water-carrying capacity of the Cowlitz was reduced by 85 percent, and the
depth of the Columbia River navigational channel was decreased from 39
feet to less than 13 feet, disrupting river traffic and choking off ocean
shipping” (Carson 1990, 50; Tilling, Topinka, and Swanson 1990). The ash
fall in eastern Washington, Idaho, and Montana destroyed crops, damaged
equipment, and disrupted commerce. According to MacCready (1981),
total damages amounted to nearly $1 billion. The federal government bore
54 percent and the private sector about 33 percent of these costs. Most of
the costs were timber and clean-up costs (84%).
Natural Disasters - Geological
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Tsunamis.
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A tsunami is a series of waves generated by an undersea
disturbance such as an earthquake. Tsunamis also can
be caused by volcanic eruptions and landslides.
Like ripples in a pond, but on a vastly larger scale.
Areas at greatest risk are less than 50 feet above sea
level and within one mile of the shoreline.
They arrive as a series of successive crests from 5 to 90
minutes apart with crests and troughs.
2004 Indian Ocean Tsunami
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The Earthquake, Tsunami, Damage, and
Casualties.
2004 Tsunami video – Phuket, Thailand.
Natural Disasters – Other Geological
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Landslides.
Expansive soils.
Medical Disasters
Epidemics occur when an infectious disease
spreads beyond a local population, lasting longer
and reaching people in a wider geographical area.
When that disease reaches worldwide
proportions, it's considered a pandemic. Several
factors determine whether an outbreak will
explode into an epidemic or pandemic: the ease
with which a microbe moves from person to
person, and the behavior of individuals and
societies.
Medical Disasters
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On the global level, different populations
interact through travel, trade, and war—all
opportunities for microbes to reach new
areas. Rapidly growing cities also allow
microbes to infect large groups of people.
Of course, in many situations, individual
and communal behavior also contribute to
the spread of disease.
Medical Disasters
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WHAT MAKES A PANDEMIC?
Pandemics, such as the 14th-century
plague known as the Black Death, have
been occurring for centuries. The Black
Death devastated populations throughout
Asia and Europe. And the influenza
epidemic of 1918-19 caused at least 20
million deaths worldwide. AIDS, of course,
can be found in almost every country.
Medical Disasters
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Several factors contribute to the global spread of an
infectious disease. First, it depends on how easily the
disease-causing microbe is transmitted from person to
person. For example, the tuberculosis microbe moves
through a population much more slowly than the influenza
microbe.
Some microbes live inside an animals, such as mosquitoes
or mice, during part of their life cycle. The habitat and life
cycle of that animal can limit or extend the range of the
microbe.
Human behavior and public health conditions are also
important factors. Reusing needles for injecting vaccines or
drugs increases risk of infection, as does using water from a
polluted source.
Medical Disasters
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WAR
Warfare has long been linked to disease. In
fact, infectious diseases sometimes kill
more soldiers than do battle wounds.
Infected soldiers allow microbes to enter
new ecosystems and infect civilians,
sometimes with disastrous results. Soldiers
may also pick up infections abroad and
carry them back home.
Medical Disasters
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During a war, civilian populations are equally at
risk from the breakdown of infrastructure and
public health systems, and the scarcity of
medicine. People are often forced from their
homes into crowded, unsanitary refugee camps.
If that isn't enough, warfare also destroys
ecosystems. Animals carrying disease-causing
microbes may thrive in such altered
environments.
Medical Disasters
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TRADE, TRAVEL, AND MIGRATION
Throughout history, travelers moving about the
world for work, adventure, or resettlement have
spread disease. Microbes that infest insects and
rodents stowaways—on ancient merchant ships
to modern jet planes—have also spread disease.
And other disease-causing microbes can lodge in
the huge quantity of foods, lumber, and other
trade goods that are always moving across the
globe.
Medical Disasters
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CITIES
Cities bring many people into close contact,
making it easier for disease-carrying microbes to
circulate, especially among poor people crowded
together in unsanitary conditions. And in rapidly
growing cities, particularly those in developing
countries, public health programs often lack the
resources to reach the people who need the most
help. Lack of access to vaccinations, medicines,
and public health information all contribute to the
spread of microbe-caused diseases.
Medical Disasters
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WEATHER AND CLIMATE CHANGE
Human behavior, combined with changes in
weather patterns, contribute to the spread
of infectious diseases. Both can produce
conditions that lead to increases in
disease-causing microbes and the animals
that carry then.
Medical Disasters - AIDS
Medical Disasters – 1918 Influenza
Pandemic
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The Influenza Pandemic of 1918.
Technological Disasters
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Fires.
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1,602,000 in 2005.
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50 percent outside or other.
32 percent structural fires.
18 percent vehicle fires.
82 percent of all fire fatalities occur in the home.
Hazardous material incidents.
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Explosives, flammable and combustible substances,
poisons, and radioactive materials.
Released because of transportation or plant accidents.
Technological Disasters
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Nuclear accidents.
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Potential danger from radiation exposure.
Terrorism.
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Use of force or violence against persons or
property in violation of the criminal laws of the
U.S. for purposes of intimidation, coercion, or
ransom.
Prior to 9/11, most attacks involved bombing.
Domestic versus international terrorism.
Technological disasters
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Weapons of mass destruction (WMDs).
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CBRN (chemical, biological, radiological, nuclear).
Chemical agents.
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Biological agents.
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Pulmonary, blood, vesicants (blister), nerve, incapacitating,
riot-control (irritant).\
Bacteria, viruses, toxins.
Radiation threat.
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Dirty bomb, radiation dispersion device (RDD).
Risk Assessment
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Risk definition
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The probability and frequency of a hazard occurring.
The level of exposure of people and property to the
hazard.
The effects or costs, both direct and indirect, of this
exposure.
Approaches
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Risk matrix (qualitative).
Composite exposure indicator (CEI) approach.
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14 indicators (infrastructure).
Risk Assessment
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Identify and characterize the hazard.
Evaluate each hazard for severity and frequency.
Estimate the risk (human and built environment).
Determine the potential societal and economic
(direct) effects and the indirect effects or costs.
Determine the acceptable level of risk.
Identify risk reduction opportunities.
Social Vulnerability
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Religion
Age
Gender
Literacy
Health
Politics
Security
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Human rights
Government and
governance
Social equality and
equity
Traditional values
Customs
Culture
Economic vulnerability
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Debt
Access to credit
Insurance coverage
Sources of income
Funds reserved for disaster
Social distribution of wealth
Business continuity planning