What Makes a Hurricane?

  • By Ana Aceves
  • Posted 11.15.17
  • NOVA

Hurricanes bring wind, rain, and destruction—but how do they form?

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Running Time: 01:20

Transcript

What Makes a Hurricane?

Published November 15, 2017

Onscreen: Hurricanes

Massive whirling storms in the Atlantic and N.E. Pacific

With wind speeds over 74 mph

Bringing torrential rain, thunder and lightning.

The strongest hurricanes exceed wind speeds of 157 mph and can demolish nearly everything in their path.

What makes a hurricane?

1. Warm water needs to extend at least 200 feet into the ocean.

Kerry Emanuel: The hurricanes churn up cold water from beneath the warm water on the surface, so they cool the surface, it’s like throwing cold water on a fire.

Onscreen: 2. The cross winds near the top of the hurricane—called wind shear—can’t be too strong.

Kerry: That tends to blow dry air into the core of a hurricane that also is like throwing cold water on the fire.

Onscreen: 3. Hurricanes need moisture throughout the atmosphere. Then wind speeds rise within the eye of the hurricane.

Many factors can affect hurricane formation…including the climate.

A warmer climate will bring increased intensity of tropical storms.

Storms may not be more frequent…But the storms that do occur will tend to be more intense.

Credits

PRODUCTION CREDITS

Digital Producer
Ana Aceves
KILLER HURRICANES
Series Producer and Director
Oliver Twinch
Filming and Directing
Paul Williams
Editor
Ben Lavington Martin

FOOTAGE AND GRAPHICS

Visuals
AP
Getty
NASA
Pond5

SFX

Music
­APM

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