As Hurricane Dorian heads toward the US mainland, does anyone wonder why hurricanes have names? And how are the names decided?
A hurricane is a tropical cyclone formed over the North Atlantic Ocean and Northeast Pacific. It's the same phenomena as a typhoon, which is formed over the Northwest Pacific Ocean, and a cyclone, which is formed over the South Pacific and Indian Ocean.
But whatever they are called, all tropical cyclones generate in the same mechanism.
NASA Science says a tropical cyclone is like a giant engine while warm, moist air is fuel. The first 50 meters water below the surface must be at least 80 degrees F, and then the moisture evaporates from the ocean in a cluster. The warm water cools down in the air and concentrates into dense, towering vertical clouds.
Hurricane categories. /Designed by CGTN's Qu Bo
Wind acts as a catalyst in the process to sweep water vapor from the surface. The whole system begins to spin with the help of the earth's rotation and air pressure. When the wind speeds reach 74 mph, a hurricane forms.
A hurricane is not a living organism but it also has its own life cycle and can travel thousands of miles from ocean to land. It can keep growing if it absorbs optimal wind and warm, moist air.
From its birth to death, a hurricane can last a day or as long as a month.
So back to our first question: Why do hurricanes have names?
It is because tropical cyclones like hurricanes or typhoons last a long time. Giving them names can help people identify them. Their names are decided in alphabetical order, with the name of the first storm of a year beginning with A, the next with B and so on.
Tropical Atlantic Ocean Cyclone Names. /Designed by CGTN's Qu Bo
About Natural Phenomena
Natural Phenomena is a new series that takes you to an unknown world of natural phenomena. From natural disasters such as earthquakes and volcanic eruptions to spectacles like aurora and mirage, let's dig into the secret of our planet.
(Cover image is Hurricane Dorian. /VCG Photo)
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