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Natural Disasters

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Title: Natural Disasters


1
Natural Disasters
  • Natural disasters by far account for the greatest
    loss of life and the greatest amount of property
    damage than any other type of event.
  • The United States is becoming more vulnerable to
    natural hazards mostly because of changes in
    population and national wealth density--more
    people and infrastructure have become
    concentrated in disaster-prone areas.

2
Worst Earthquake
  • July 28, 1976 - The world's most devastating
    quake of the 20th century (magnitude 7.8) hit the
    sleeping city of Tangshan, in northeast China.
  • The official death toll was 242,000.
  • Some unofficial estimates put the actual number
    of dead as high as 655,000.

3
Worst Volcano
  • May 8, 1902 - Mt. Pelee erupted on the Caribbean
    island of Martinique, destroying the capital city
    of St. Pierre. Up to 40,000 were killed.

4
Worst Flood
  • July-August 1931 - Massive flooding of China's
    Yangtze River led to more than three million
    deaths from drowning, disease and starvation.

5
Worst Pandemic
  • 1918-1919 - An epidemic of "Spanish Flu" spread
    around the world. At least 20 million died,
    although some estimates put the final toll at 50
    million.
  • It is estimated that between 20 per cent and 40
    per cent of the entire world's population got
    sick.

6
Worst US Flood
  • 1889
  • May 31, Johnstown, Pa. collapse of South Fork
    Dam left more than 2,200 dead.

7
Worst US Hurricane
  • 1900
  • Sept. 8, Galveston, Tex. an estimated
    6,0008,000 dead, mostly from devastation due to
    tidal surge.

8
Worst US Tornado
  • 1925
  • March 18, Mo., Ill., and Ind. great Tri-State
    Tornado 689 dead over 2,000 injured. Property
    damage estimated at 16.5 million.

9
Worst US Earthquake
  • 1906
  • April 18, San Francisco earthquake accompanied
    by fire razed more than 4 sq mi estimates range
    from 700 to 3,000 dead or missing.

10
Natural Disasters
  • Natural hazards are more predictable than any
    other hazard.
  • Although may not know exactly when a natural
    disaster will occur, precisely where they will
    strike, or how severe they will be, past
    experience can be used to identify areas that are
    most vulnerable to certain types of natural
    disasters.

11
Natural Disasters
  • The largest single category of repetitive threats
    results from weather or geological events that
    can affect any area of the country.
  • Their impact can be localized or widespread,
    predictable or unpredictable resulting damage
    can range from minimal to major.

12
Natural Disasters
  • Depending on the severity of the incident, they
    can have a long-term impact on the infrastructure
    (roads, bridges, and utilities) of any given
    location.
  • Threats involving landslide, tornado, tsunami,
    volcano, wildlife, thunderstorm, and winter
    storm.

13
Natural Disaster Planning
  • Specifically, the following steps are involved in
    the process
  • Writing a management policy
  • Organizing a planning committee
  • Identifying perils or threats and assessing
    vulnerability to these hazards
  • Assessing the availability and capabilities of
    public emergency services, company personnel, and
    equipment resources
  • Deciding the level of response capability based
    upon local needs and regulatory requirements
  • Organizing the emergency response team
  • Writing the plan
  • Training personnel
  • Testing the plan

14
Earthquakes
  • An earthquake is a wave-like movement of the
    earth's surface.
  • The earth's crust and upper part of the mantle
    are consistently pushing and moving against one
    another along what are known as fault lines.
  • When rock masses slip along a fault, the energy
    of an earthquake is released in seismic waves.
  • An earthquake also can be produced by volcanic
    eruptions. Earthquakes can be extremely violent.

15
Interstate highway collapse in 1989 San Francisco
Earthquake where 41 motorists were killed.
16
Richter Scale
  • Richter scale, invented by Charles F. Richter in
    1934.
  • The damage caused by an earthquake depends on its
    severity or intensity.
  • The most widely known indicator of severity, the
    Richter scale, measures the energy released
  • A change of one full point in the Richter scale
    represents a difference factor of about 30 in
    energy released.
  • Thus, an earthquake of magnitude 7 is roughly 30
    times as powerful in terms of energy released
    as one of magnitude 6.

17
Richter Scale
Richter Magnitudes Earthquake Effects
Less than 3.5 Generally not felt, but recorded.
3.5-5.4 Often felt, but rarely causes damage.
Under 6.0 At most slight damage to well-designed buildings.
Can cause major damage to poorly constructed buildings over small regions.
6.1-6.9 Can be destructive in areas up to about 100 kilometers across where people live.
7.0-7.9 Major earthquake. Can cause serious damage over larger areas.
8 or greater Great earthquake. Can cause serious damage in areas several hundred kilometers across.
18
Modified Mercalli (MM) Intensity scale
  • Another scale is the Mercalli scale.
  • Invented by Giuseppe Mercalli in 1902
  • Today, geologists use what is known as the
    Modified Mercalli (MM) Intensity scale to measure
    the intensity of ground shaking at a particular
    site.

19
Signs and Warnings
  • Earthquakes usually occur without warning.
  • Earthquake monitoring is conducted by the U.S.
    Geological Survey, the National Oceanic and
    Atmospheric Administration, and universities
    throughout the United States.
  • However, the exact time and place an earthquake
    will occur still cannot be precisely.

20
Earthquake Risk Maps
  • Though quakes usually strike without warning,
    scientists have produced risk maps that show
    areas where an earthquake is likely to occur.
  • Other clues to the probability of a quake come
    from studying faults, measuring the tilt of the
    earth's crust, watching changes in the water
    levels of wells, and even observing the behavior
    of animals.

21
Immediate Dangers
  • The actual movement of the ground is seldom the
    direct cause of death or injury.
  • Earthquake-related casualties are commonly caused
    by
  • partial or total building collapse, including
    toppling chimneys or walls, falling ceiling
    plaster, light fixtures, and pictures
  • flying glass from broken windows and skylights
    (this danger may be greater from windows in
    high-rise structures)
  • overturned bookcases, fixtures, and other large
    furniture and appliances
  • fires from broken chimneys and broken gas lines
  • fallen power lines and
  • an inappropriate or drastic human reaction caused
    by fear.

22
Secondary Emergencies
  • Fires caused by earthquakes are particularly
    dangerous.
  • Water mains may be broken and fire-fighting
    equipment may be unable to reach the fire.
  • Broken gas lines often are a major cause of
    earthquake-related fires. Damage to buildings,
    utility lines, bridges, or dams.
  • Water supplies can become contaminated by seepage
    around broken water mains.
  • Damage to roadways and to other means of
    transportation may create food and other resource
    shortages if transportation is interrupted.

23
Advanced National Seismic System Network
  • The Advanced National Seismic System Network will
    be a nationwide network of at least 7000 shaking
    measurement systems, both on the ground and in
    buildings.

24
Advanced National Seismic System Network
  • Provide emergency response personnel with
    real-time earthquake information.
  • Provide engineers with information about building
    and site response.
  • Provide scientists with high-quality data to
    understand earthquakeprocesses and solid earth
    structure and dynamics.

25
Seismic Probability MapsU.S. Geological Survey
  • Hazard maps are available from the US Geological
    Survey
  • http//earthquake.usgs.gov/research/hazmaps/produc
    ts_data/images/nshm_us02.gif

26
Floods
  • Floods can be slow or fast rising.
  • They are sometimes seasonal, as when winter or
    spring rains and melting snow fill river basins
    with too much water too quickly.
  • Flash floods are usually the result of extremely
    heavy rain or snow and are sudden.

27
1993 Mississippi Flood
  • The 1993 midwest flood was one of the most
    significant and damaging natural disasters ever
    to hit the United States.
  • Damages totaled 15 billion, 50 people died,
    hundreds of levees failed, and thousands of
    people were evacuated, some for months.

28
Comparison Photos of the Mississippi, 1993
29
Mississippi and Missouri River Basin, 1993
30
Flood Experiences
  • On the average, each year more than 300,000
    people are driven from their homes by floods, 200
    flood-related fatalities occur, and 2 billion in
    total flood damages are sustained.
  • The worst recorded flood in terms of loss of
    lives was the 1889 flood in Johnstown,
    Pennsylvania, which resulted in the loss of more
    than 2,200 lives.

31
FEMA Map Services
  • Special flood hazard areas for some 18,000
    communities are identified on a Flood Hazard
    Boundary Map or a Flood Insurance Rate Map issued
    by FEMA.
  • Many maps provide base flood elevations.

32
Floodways
  • FEMA also provides many communities with data to
    help them designate floodways.
  • The floodway is that part of the stream channel,
    plus any adjacent floodplain land, that must be
    reserved in order to allow the discharge of the
    base flood ("100-year flood") without increasing
    flood heights.

33
National Flood Insurance Program
  • Every community participating in the National
    Flood Insurance Program (NFIP) is required to
    maintain a repository for their flood maps.
  • The NFIP is a Federal program enabling property
    owners to purchase flood insurance.
  • FEMA administers the NFIP in communities
    throughout the United States.
  • Communities in the NFIP must require new
    buildings in the special flood hazard area to be
    constructed so that the lowest floor will be
    located at or above the base flood elevation.

34
Signs and Warnings
  • A flood may be build in areas near streams and
    rivers
  • Monitor radio for flood forecasts
  • Flash floods occur swiftly.
  • Flood warnings are issued by the National Weather
    Service.
  • Local police, the sheriff, the highway patrol,
    the county flood control district office, and
    other local agencies may also supply flood
    warnings.

35
Signs and Warnings
  • A flash flood watch is issued when flash flooding
    is possible within the designated watch area be
    alert
  • A flash flood warning is issued when a flash
    flood has been reported or is imminent take
    necessary precautions
  • A flood warning is issued as an advance notice
    that a flood is imminent or is in progress at a
    certain location or in a certain river basin.

36
Immediate Dangers
  • The immediate danger from flash floods is from
    the strength of the water current as it surges
    through an area, carrying debris and causing
    injuries and drowning
  • Floods can interrupt power, disable fuel sources,
    and make roads impassable. People may be stranded
    in their homes, or be unable to reach their
    homes.

37
Long Term Dangers
  • Long-term dangers include the outbreak of
    disease, widespread animal death, broken sewage
    lines and widespread water supply pollution
    broken gas lines, downed power lines, and fires.
  • Large-scale flooding can disrupt a community for
    a long time while utilities are restored, debris
    is cleared, and property is repaired.

38
Preparedness
  • Stockpile emergency building materials such as
    sandbags, plywood, plastic sheeting, and lumber.
  • Develop an evacuation and preparedness plan.
  • If in a flash flood area, have several alternate
    routes to ensure rapid evacuation.
  • Maintain emergency supplies such as a first aid
    kit, portable radio,
  • Store drinking water in jugs and bottles.

39
Prevention
  • Avoid building in a floodplains
  • Implement flood prevention strategies into
    building designs and equipment designs

40
Mitigation
  • FEMA'S The Mitigation Division manages the
    National Flood Insurance Program (NFIP) and a
    range of programs designed to reduce future
    losses to homes, businesses, schools, public
    buildings and critical facilities from floods,
    earthquakes, tornadoes and other natural
    disasters.
  • Mitigation includes such activities as
  • Complying with or exceeding NFIP floodplain
    management regulations.
  • Adopting zoning ordinances that steer development
    away from areas subject to flooding, storm surge
    or coastal erosion.

41
Response
  • As flood waters rise, take these key precautions
  • Secure all outdoor items or store them inside on
    upper levels
  • Move all valuable household possessions to upper
    levels away from rising floods.
  • Move cars, machinery, and all livestock to higher
    ground
  • Check emergency food and water supplies keep
    them high and dry.
  • Listen to radio announcements from emergency
    officials. If you are told to evacuate, do so
    immediately.
  • Do not attempt to drive over a flooded road
  • In a flash flood warning, move immediately to
    high ground.
  • Because of the speed with which a flash flood
    travels, there is no time to save any possessions
    or implement any precautionary measures.

42
Recovery
  • Have all drinking water tested by local health
    authorities before using.
  • Before entering a building, check for structural
    damage make sure it is not in danger of
    collapsing.
  • Check utilities
  • Report broken utility lines to appropriate
    authorities
  • Keep in mind that floods can cause landslides,
    mudflows, and power outages

43
Tornadoes
  • Tornados are relatively short-lived local storms.
  • They are composed of violently rotating columns
    of air that descend in the familiar funnel shape
    from thunderstorm cloud systems.
  • The weather conditions that tend to generate
    tornados are unseasonably warm and humid earth
    surface air, cold air at middle atmospheric
    levels, and strong upper-level jet stream winds.
  • Tornados can occur anywhere in the United States
    during any month of the year.
  • The destruction path of a tornado averages about
    250 yards in width and 15 miles in length.
  • However, in extreme conditions, a tornado may
    travel more than 300 miles and leave a path of
    total destruction more than a mile wide.
  • Tornados will travel up to sixty miles per hour,
    with wind speeds approaching 400 miles per hour
    within the tornado's center.

44
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45
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46
SKYWARN Spotters Network
  • To obtain critical weather information, the
    National Weather Service of the U.S. Department
    of Commerces National Oceanic and Atmospheric
    Administration, and cooperating organizations,
    have established SKYWARN Spotter Networks

47
Greensburg, KS, June 4, 2007
  • At 945 p.m. CDT on May 4, 2007, Greensburg was
    hit by an EF5 tornado.
  • The tornado was estimated to be 1.7 miles in
    width and traveled for nearly 22 miles.
  • Ninety-five percent of the city was confirmed to
    be destroyed, with the other five percent being
    severely damaged.
  • The National Weather Service estimated winds of
    the tornado to reach 205 mph.
  • Twelve fatalities were attributed to the tornado,
    ten of them residents of Greensburg.
  • Tornado sirens sounded in the city twenty minutes
    before the tornado struck, and a tornado
    emergency was issued, which undoubtedly saved
    many lives.

48
Greensburg, KS, June 4, 2007
49
Tornado Myths
  • MYTH Areas near rivers, lakes, and mountains are
    safe from tornadoes. FACT No place is safe from
    tornadoes. In the late 1980's, a tornado swept
    through Yellowstone National Park leaving a path
    of destruction up and down a 10,000 ft. mountain.
  • MYTH The low pressure with a tornado causes
    buildings to "explode" as the tornado passes
    overhead.FACT Violent winds and debris slamming
    into buildings cause most structural damage.
  • MYTH Windows should be opened before a tornado
    approaches to equalize pressure and minimize
    damage.FACT Opening windows allows damaging
    winds to enter the structure. Leave the windows
    alone instead, immediately go to a safe place.

50
Signs and Warnings
  • Tornados develop during severe thunderstorms and
    hurricanes.
  • While not all thunderstorms and hurricanes create
    tornados, the potential is there.

51
The Enhanced Fujita Scale
  • The Fujita Scale is used to classify the
    intensity and damage from tornadoes.
  • Developed in 1971 by Tetsuya "Ted" Fujita
  • Through extensive research the Fujita Scale was
    developed based on damage, not wind speeds
  • Storm researchers came up with the Enhanced
    Fujita scale to better reflect a tornados
    strength.
  • The new Enhanced Fujita scale started use in
    February  2007.

52
Tornado Watches and Warnings
  • The National Severe Storms Forecast Center in
    Kansas City, Missouri, issues tornado watches.
  • Local National Weather Service offices issue
    tornado warnings.
  • Local officials may sound sirens in a tornado
    warning.
  • A tornado watch indicates that conditions are
    right for a tornado to develop and that the sky
    should be watched.
  • A tornado warning indicates a tornado has been
    sighted or is spotted on radar.
  • Warnings will give the location of the tornado
    and the area immediately affected by the warning.

53
Immediate Dangers
  • The immediate threat from tornados is danger to
    life and damage to property from violently
    whirling winds and debris hurled through the air
    by winds.

54
Long-Term Dangers
  • Long-term risks include the possibility of
    building collapse, fallen trees and power lines,
    broken gas lines, broken sewer and water mains,
    and the outbreak of fires.
  • Agricultural crops and industries may be damaged
    or destroyed.

55
Preparedness
  • The best preparation for a tornado is to
    designate a safe place as a tornado shelter.
  • Tornado shelters are safest if they are
    underground.
  • A basement away from windows offers the best
    protection.
  • If neither of these are available, plan to find
    shelter under heavy furniture near an inside wall
    on the ground floor.
  • Get under solid furniture.

56
Prevention
  • Follow relevant building code practices such as
    the use of wind-resistant design.

57
Response
  • Get to adequate shelter immediately
  • Do not drive.
  • If driving in a city and spot a tornado, get out
    of your car and go into a nearby building.
  • If driving in open country, drive at a right
    angle away from the tornado's path if you can
    safely do so.
  • Do not try to outrun the storm.
  • If you cannot avoid the tornado, get out of your
    car.
  • Lie flat in the nearest depression, such as a
    ditch, culvert, or ravine.
  • Protect your head, and stay low to the ground.

58
Recovery
  • Communicating with employees, vendors and clients
  • Recovering documents and electronic data
  • Protecting equipment and physical resources
  • Locating alternate physical facilities
  • Finding alternate suppliers/ sources of raw
    materials
  • Maintaining cash flow
  • Addressing legal issues
  • Processing insurance and medical claims.

59
Hurricane Preparedness
  • Hurricane hazards come in many forms
  • storm surge
  • high winds
  • tornadoes
  • flooding

60
Storm Surge
  • Storm surge is simply water that is pushed toward
    the shore by the force of the winds swirling
    around the storm. This advancing surge combines
    with the normal tides to create the hurricane
    storm tide, which can increase the mean water
    level 15 feet or more.

61
Storm Surge
  • One tool used to evaluate the threat from storm
    surge is the SLOSH model.

62
Hurricane Katrina
63
SLOSH Model
  • SLOSH (Sea, Lake and Overland Surges from
    Hurricanes) is a computerized model run by the
    National Hurricane Center (NHC) to estimate storm
    surge heights and winds resulting from
    historical, hypothetical, or predicted hurricanes
    by taking into account
  • Pressure
  • Size
  • Forward speed
  • Track
  • Winds

64
Hurricane Katrina
65
SLOSH Model
  • The SLOSH model is generally accurate within plus
    or minus 20 percent. For example, if the model
    calculates a peak 10 foot storm surge for the
    event, you can expect the observed peak to range
    from 8 to 12 feet.

66
High Winds
  • Hurricane intensity measured on the
    Saffir-Simpson Scale
  • The scale was developed in 1971 by civil engineer
    Herbert Saffir and meteorologist Bob Simpson, who
    at the time was director of the U.S. National
    Hurricane Center (NHC).
  • Categories 1-5
  • Based upon wind speeds

67
Hurricane Katrina
68
Estimating Potential Damage from Disasters
  • FEMAs HAZUS-MH
  • Potential loss estimates analyzed in HAZUS-MH
    include
  • Physical damage to residential and commercial
    buildings, schools, critical facilities, and
    infrastructure
  • Economic loss, including lost jobs, business
    interruptions, repair and reconstruction costs
    and
  • Social impacts, including estimates of shelter
    requirements, displaced households, and
    population exposed to scenario floods,
    earthquakes and hurricanes.
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