Transcript Hurricanes Thunderstorms and Tornadoes ppt

Hurricanes, Thunderstorms, and
Tornadoes
What is a hurricane?
• A hurricane is a large, swirling, lowpressure system that forms over the warm
Atlantic Ocean.
What things make hurricanes lose
strength?
• 1. Crumple a piece of paper, then flatten it out.
Crumple and flatten it out again.
• 2. Spin the top on the flattened paper.
• 3. Spin the top on a smooth surface. Count the
seconds until it stops spinning.
What do you think?
How does the texture of the surface
affect the rate at which the top loses
energy?
Hurricanes form over warm ocean
water.
• Near the equator, warm ocean water
provides the energy that can turn a
low pressure center into a violent
storm.
• As water evaporates from the ocean,
energy moves from the ocean water
to the air. This energy makes warm
air rise faster.
• Tall clouds and strong winds develop.
• As winds blow across the water from
different directions into the low, the
Coriolis Effect bends their path into a
spiral.
• The winds blow faster and faster,
around the low, which becomes the
center of a storm system.
Parts of a Hurricane
Create a Model of a Hurricane!
• Using glue, blue construction paper, and
cotton balls, create a model of a hurricane,
labeling and explaining each part.
• You may use your graphic organizer for
assistance!
Why do hurricanes seem to die
over land?
• As long as a hurricane is over
water, the warm, moist air rises
and provides energy for the
storm.
• When a hurricane reaches land,
however, its supply of energy
disappears and the storm loses
power.
Air On The Move
• Wind is moving air. Warm air rises, and
cool air comes in to take its place. This
movement creates the winds around the
globe. Winds move at different speeds and
have different names based on their
speed. Winds are also grouped by their
direction. Easterly winds blow from east to
west, while westerly winds blow from west
to east.
Tornadoes
Tornadoes
• The fastest
recorded wind
speed is 230 miles
per hour and
occurred in New
Hampshire in 1934.
Although, winds
can get faster in
tornadoes. The
windiest place in
the world is in
Antarctica.
Thunderstorms
• It is late afternoon. The white puffy clouds
that have been growing all day are
replaced by a greenish sky. A distant
rumble is heard...then another. It starts to
rain. A flash of light streaks the sky,
followed by a huge BOOM. Welcome to a
thunderstorm.