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Tropical Cyclones
Have you ever seen a TV weatherperson pointing to a large, white spiral of storm clouds spinning over the Earth on their video screen? If so, then you've gotten a small look at what the most powerful storm in the world looks like: a tropical cyclone. (热带风暴)
The warm air and water at the equator(赤道) rise into the atmosphere, cool off, and then sink back down. As this cycle repeats itself over and over again, the storm begins to grow and the winds around the storm begin to move faster.
Depending on where a tropical cyclone is in the world, it is called either a hurricane, a typhoon, or a cyclone. If tropical cyclones move over the northwestern Pacific Ocean, they're called typhoons. In the South Pacific or the Indian Ocean, they're called cyclones.
The center of a tropical cyclone is called the "eye". Most of the strong winds do not reach the eye of the storm, so the eye is the calmest part.
A storm that is rated as a Category 1 is the weakest. A Category 5 tropical cyclone is the strongest, which has winds of over 300km per hour, can cause catastrophic damage.
Once these storms come onto land, they no longer have the warm ocean water they need to grow larger. This means that they begin to grow weaker. This doesn't stop them from causing a lot of damage before they go away.
A. They still may produce strong rain and tornadoes.
B. Tropical cyclones are categorised based on their strength.
C. They withdraw as quickly as they arrive and leave the land untouched.
D. The rest of the storm moves in a circle around the eye at incredibly high speeds.
E. Tropical storms with wind speeds that reach 74 miles per hour are called hurricanes.
F. Tropical cyclones start as tropical storms that form in warm ocean waters near the Earth's equator.
G. Such storms moving over the northeastern Pacific or the Atlantic Ocean are termed hurricanes.