Birth of a Monster

The air that surrounds our planet weighs 5,000,000,000,000,000 tons! In words, that is 5 quadrillion tons and that's a lot. This air is always moving. It swirls, blows, sinks, and rises. In summer and early fall, great masses of air sit over the warm, tropical oceans. If a mass of air gets warmer and picks up lots of moisture, it can start swirling. When this happens, a HURRICANE or a ONE-EYED MONSTER is born. If the hurricane moves toward the continent, it could wipe out everything in its path.

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Hurricanes are tropical cyclones that can cover thousands of square miles. The winds in a hurricane exceed 74 miles per hour and circulate counter-clockwise about its center in the Northern Hemisphere or clockwise in the Southern Hemisphere. Hurricane-like storms are called by different names in the different regions of the world. Wind belts and highs and lows all help direct the journeys of tropical cyclones.

How does a "one-eyed monster" form? Actually, there are several ingredients needed for a hurricane to form.

  • Tropical Ocean Water (at least 500 kilometers or 300 miles from the Equator)

  • Heat from the Sun

  • Air

  • Wind

  • The Spin of the Earth

Follow the steps below through the life cycle of a hurrricane.

A Monster is Born

Step 1. The sun warms the ocean water to 81 degrees Fahrenheit or 26.5 degrees Celsius. Step 2. The ocean water evaporates caused by the heat from the sun. The evaporating water forms a cloud of warm, moist air that moves upward.
Step 3. As the warm, moist air rises, more air rushes in to replace it. This air is also heated and moistened by the ocean surface. It begins to rise and form clouds, heating the air around it. Step 4. Eventually, a large mass of warm, moist air with rain clouds is formed over the ocean. The warm air expands and becomes less dense and lighter and forms an area of low pressure.
Step 5. More warm, moist air rushes in from the ocean surface. The air begins to spin because of the rotation of the earth. The air goes faster and faster as it spirals inward. Step 6. The whole storm, now spinning like a top, is carried across the ocean by the wind. As it moves across the warm ocean waters, it will continue to become stronger and stronger.
Step 7. Finally, it moves over land or cold water. It loses its fuel source, warm ocean, and begins to die out.

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