Download 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