- Slides: 12
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 • 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.