DISASTERS

							NATURAL DISASTERS

 IN THE UNITED STATES
     NATURAL DISASTERS
     What is a natural disaster?
• Is what happens when nature causes
  damage.
• A hurricane can be a natural disaster.
• Most natural disasters happen suddenly.
• They can wreck homes and property.
• People can get hurt.
               VOLCANOES
• A hole in the earth’s crust from
  which hot or melted rock and steam
  come
• The word “volcan” in Roman
  mythology means god of fire.
• Many are found in a big curve that
  goes around the Pacific ocean. The
  scientists name the curve The Ring.
• The liquid inside the volcano is
  called magma. It is hot melted rock.
  When it is out the volcano’s mouth
  is called lava.
              CYCLONES
• It often cover thousands of square miles.
• The winds blows toward the center of an
  area of low air pressure.
• Cyclones blow in spirals because of the
  rotation of the earth.
• The direction of turn is counterclockwise in
  the Northern Hemisphere and clockwise in
  the Southern Hemisphere.
             TORNADOS
• Sometimes miscalled cyclones, arise when
  conditions that cause thunderstorms are
  usually violent.
• Winds blowing in opposite directions
  around a strong updraft start a narrow,
  violent whirl.
• Centrifugal force throws the air away from
  the center, leaving a core of very low
  pressure.
       THUNDERSTORMS

• Are local disturbances usually covering
  only a few square miles.
• Extremely common in many parts of the
  world. Most of North America.
• Composed of one or more meteorologists
  call cells.
• The duration of thunderstorm is short,
  usually lasting only 30 to 40 minutes.
EARTHQUAKES
• The sudden shaking of the
  ground that occurs when masses
  of rock change position below
  the earth’s surface is called an
  earthquake.
• The shifting masses send out
  shock waves that may be
  powerful enough to alter the
  surface of the earth.
 Earthquakes in the united states
(In 1906 the SAN FRANCISCO)
• San Francisco
  earthquake, when 521
  blocks in the city
  burned uncontrollably
  for three days.
• San Francisco,
  California in 1989 an
  earthquake caused
  great destruction and
  lost
              HURRICANES
• Any wind that blows
  more than 75 miles per
  hour.
• Characterized by
  strong winds and
  torrential rains.
• After it roars ashore, it
  looks like at though
  the storm has ended
  when the eye passes
  overhead.
   SIGNS OF A HURRICANE
• First come dull sunset, caused by a thin
  haze of clouds.
• Then the air becomes hot and sticky.
• The barometer is high, and the winds dies.
• At sea there is a growing swell.
• Next the barometer drops suddenly,
  signaling a rapid change from high pressure
  to low pressure.
• last a deluge of rain fills the air with strong
  winds.
       HURRICANES IN THE
         UNITED STATES
• Lake okeechobee,
  Florida in Sept. 16-17,
  1928. Miles of dikes
  collapsed; lake spilled
  onto farmland.
• In New England in
  September 23, 1938.
  Damage homes and
  crop.
      HURRICANES IN U.S.
        CONTINUES...
• On June 27, 1957 in Louisiana. Hurricane
  Andrew slammed into the Golf coast but
  residents ignored warnings and threw
  parties instead of evacuating. More than
  7000 people die.
• In August 14-22, 1969 in the U.S. Gulf
  coast hurricane Camille roared through
  Louisiana, Mississippi and Alabama. More
  than 500, 000 people death.
 MORE HURRICANES IN U.S.
• In September 16-22, 1989 hurricane Hugo
  wreaked path of destruction through
  Caribbean island lashing South and North
  Carolina. More than people 500 dead and
  the damage of property was estimated in the
  billions of dollars.
• In September 1992, the Hawaiian Island
  was hit by hurricane Iniki. The winds were
  225 miles per hour. Estimated $2 billion in
  property damage.
                 CYCLONE
• Winds blow toward
  the center of an area of
  low air pressure.
• They blow in spirals.
• They are deflected by
  the rotation of the
  earth.
• The direction is
  clockwise
  counterclockwise