Hurricanes are the most powerful storms in the Earth’s atmosphere. The storms have different names depending on where they take place. Scientists call all these storms tropical cyclones.
If the storms form over the Atlantic Ocean or eastern Pacific Ocean, they are called hurricanes. Storms that form in the western Pacific Ocean are known as typhoons. In the Indian Ocean, they are called cyclones.
Scientists at the American space agency NASA describe tropical cyclones as huge weather “engines” that use warm, moist air as fuel. They can only form over warm, tropical waters near the equator.
A tropical cyclone develops when warm moist air near the surface of the ocean rises. This creates an area of unusually low air pressure.
Higher-pressure air from surrounding areas pushes in to take the place of the warm, rising air. It becomes warmer and moister and rises, too.
The rising, moist air goes high into the atmosphere, where temperatures are low. This creates wind. The moisture forms clouds. The developing weather system begins to spin because of the Earth’s rotation.
As the storm spins faster and faster, what is called an “eye” of the storm develops at its center. This is a calm area of very low pressure. Higher pressure air from above flows down into the eye.
