Extreme Weather

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Extreme Weather

• Hurricanes

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What is a Hurricane?

• A hurricane is a tropical storm, whose winds blow
  at a speed of over 119 kph.
• In some parts of the world these storms are
  called cyclones because the winds blow in a
  spiral shape.

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Hurricane Katrina

• Recently, the south western coast of the USA
  was hit by a very big hurricane. The winds caused
  the sea level to rise so high that the water was
  able to burst through the levees surrounding the
  city of New Orleans and flood it.

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• The entire population of the city should have
  been evacuated, but unfortunately, this was not
  done in time, and hundreds of people died.

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Katrina

• Here is a satellite photo of hurricane Katrina.
  You can see the distinctive spiral shape.

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The strength of a hurricane

• In this picture, we see the effects of a
  hurricane as it grounds. The trees will soon be
  bent almost in two, and the waves will surge up
  the beach.

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The aftermath.

• A soldier surveys the damage caused by a
  hurricane in a residential area of the USA.

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The next round

• As though the Gulf Coast of the US has not
  suffered enough recently, hurricane Rita is now
  on her way, causing damage to the beleaguered New
  Orleans and Florida.

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Hurricane Watching.

• Scientists have only been studying hurricanes
  only for about 100 years. But there is evidence
  of hurricanes occurring long in the past. For
  example, geologists (scientists who study the
  earth) believe that layers of sediment in a lake
  in Alabama was brought there by a hurricane in
  the Gulf of Mexico as long as 3,000 years ago!
  There is also evidence in Florida of hurricanes
  more than 1,000 years ago.

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• One of the first human records of hurricanes
  appears in Mayan hieroglyphics. The Mayans also
  practiced a kind of mitigation and risk reduction
  by building their major settlements away from the
  hurricane-prone coastline. In fact, it is the
  Mayan word "Hurakan" that became our word
  "hurricane." Hurakan was the name of one of their
  gods, who, they believed, blew his breath across
  the water and brought forth dry land. Later,
  Carib Indians gave the name "Hurican" to one of
  their gods of evil.

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• There were a number of particularly severe
  hurricanes as the U.S. went from the 1800s to the
  1900s. Hurricanes hit Louisiana, South Carolina
  and Georgia in 1893 and killed as many as 4,000
  people. In 1900, a famous Texas hurricane killed
  more than 8,000 people and was a Category 4
  storm.
• As forecasting improved communities were no
  longer surprised by hurricanes and could take
  measures to evacuate ahead of the storm. While
  destruction still continues, the number of deaths
  in hurricanes had dropped significantly.