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Island winds, driving rain, killer waves, these are the hallmarks of a hurricane, also called cyclones or typhoons, hurricanes are giant storms prevailing the world’s tropical seas. An average hurricane releases as much energy a day as the explosion of a half million small atomic bombs. Hurricanes form in the summer or fall when the sun heats vast stretches of tropical ocean to over 82 degrees. Warm moist air rises over these hot spots, creating thunderstorms. Upper level winds and surface winds then come together, forming a circular pattern of clouds, known as a tropical depression. When the winds exceed 39 miles per hour, a tropical storm is developed. When the winds reach 74 per hour, a hurricane is officially born. Inside the storm, bands of rain are up to 300 miles long meet in the air wall, the most violent section. Here, winds up to 200 miles per hour spiral upward, within the center of the hurricane, down drops of dry air, create a strangely common area called the eye. Fully formed a hurricane-made stretch of a 500 miles in diameter. That’s the storm nearly the size of Texas and reach a height of 9 miles. Most of these storms spin out of the open sea, but in the average year, two or three will strike the mainland of North America, and when they do, the damage can be catastrophic. Most dangerous is the storm surge, a wall of water that sweeps across the coastline were a hurricane makes landfall. About 45,000 people were killed by the hurricanes in the 20th century, including some 15,000 in the United States. Hurricanes are also costly in dollars. 1992’s Hurricane Andrew was the most expensive natural disaster in US history, causing more than 25 billion dollars worth of damage. Scientists are searching for better ways to predict the path of the hurricane, special planes called hurricane hunters fly directly into these monster storms, and drop sensors to measure winds, speed, temperature and air pressure, providing vital clues to the hurricanes direction. New 3D models are also helping scientists understand this awesome force of nature. And provide quicker and more accurate warnings to anyone unlucky enough to be caught in its path.
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